1
2
  -2021
  
 
(     )
 :    : 75
:    ,             
          
-
1. ()           
()          : x3-x-3=0.
2.(a)        ?       
  
(b)    3x² + 6x-45=0      
-
3. (a)             - 
?      
() -    :


2
2




󰇛

󰇜
4. ()              
()        :
󰇛

󰇜


󰇛

󰇜

󰇛

󰇜
-
5. (a)             ?
   
(b)  (X = 0) Y           

-1
-2
2
4
-1
-9
11
69
6.(a)             
  ? 
()        1/3      :
󰆚
󰇡
󰇢

-
7. ()        
3
2
(b)      ?      ?   
:

10
20
30
40
50
60
80

32
20
25
35
40
28
45
8. (a)   ?             
()                  :

1993
1994
1995
1996
1997
1998

7
10
12
14
17
24
4
2
  -2021
  
 
(     )
 :    : 75
:    ,             
          
-
1. ()           
()          : x3-x-3=0.
::  :    
                
:
       ()         
      ,            
     
,           :
1.  :          -
              
   ,   -   
:     1/3         0.333333 ...
(     ) ,     6    
 ,   0.333333             

5
2
2.  :            ,
                
 ,    
: e^x       : e^x = 1 + x + x^2/2! + x^3/3! + x^4/4! + ...
     ( , 4  )     ,   - 
       ,          ,  
               
3.  : ,     ,        

  = |   -  |
 π    3.14159...     3.14 ,   : |3.14159 -
3.14| ≈ 0.00159
4.  : ,           
    
 = (  / | |) × %
:  π      :   = (0.00159 / 3.14159) × 100% ≈
0.0506%
5.  :                
           
:   A = πr^2            
π          r       ,    
     
6.          ,    
        
:      ,          
        
              
 :
1.       
2.      
3.         
4.     
6
2
,    
   
 :      x^3 - x - 3 = 0   
                
                 :
1.   [a, b]      f(a)  f(b)        
        
2.   c = (a + b) / 2   
3.  f(c)   
4.  f(c) = 0 ( 0    )      
5.  f(c)   f(a)   ,  a c   
6.  f(c)   f(b)   ,  b c    
7.   2-6                

,      : x^3 - x - 3 = 0
1:    f(x) = x^3 - x - 3      [a, b]
      f(a)  f(b)   
  : f(1) = 1^3 - 1 - 3 = -3 () f(2) = 2^3 - 2 - 3 = 3 ()
!   [1, 2]      
 :      ( ) 0.0001  

 1: c = (1 + 2) / 2 = 1.5 f(1.5) = 1.5^3 - 1.5 - 3 = -0.875 ()
 f(1.5) f(1)    ,        : 
: [1.5, 2]
 2: c = (1.5 + 2) / 2 = 1.75 f(1.75) = 1.75^3 - 1.75 - 3 = 0.796875 ()
 f(1.75) f(2)    ,        : 
: [1.5, 1.75]
 3:c = (1.5 + 1.75) / 2 = 1.625 f(1.625) = 1.625^3 - 1.625 - 3 = -0.119141 ()
     :  : [1.625, 1.75]
     ,        
     :
7
2
 4:c = 1.6875, f(c) = 0.319824 ()  : [1.625, 1.6875]
 5:c = 1.65625, f(c) = 0.095581 ()  : [1.625, 1.65625]
 6:c = 1.640625, f(c) = -0.013092 ()  : [1.640625, 1.65625]
 7:c = 1.648438, f(c) = 0.041058 ()  : [1.640625, 1.648438]
             0.0001    

13   ,     :  ≈ 1.6447265625 f(1.6447265625) ≈ -
0.0000047684
     ,         ,   
 
,       x^3 - x - 3 = 0    1.6447
     : 1.6447^3 - 1.6447 - 3 ≈ -0.0000047684
    ,      ,        
      
     :
1.      
2.        (     )  
    
3.               
 
,    :
1.           
2.            
3.         ,     
 ,              
            
           ,   
    :
1.   (        ):
1.6447298858494002
8
2
2.  : ≈ 1.6447265625
 = |1.6447298858494002 - 1.6447265625| ≈ 0.0000033233494002
  = (0.0000033233494002 / 1.6447298858494002) × 100% ≈ 0.000202%
   ,      ,     
 
 ,           
             
        ,        
       
 ,     ,        
      -,      , 
               
          
2.(a)        ?       
  
(b)    3x² + 6x-45=0      
:.   
1.        :
                  ,
                 
         ,       
            !
             :
)   :-             
              
b)              
 ,        
)   :            
    ,         
9
2
)   :            
  ,          
)     :  ,      
                 
2.    :  
          
     :
                   
            
 --    :
 1:        (x1, y1)  (x2, y2)   2: 
          3: x1  x2     x-  
y-          
    :
y = y1 + ((x - x1) / (x2 - x1)) * (y2 - y1)
:
x       y    
(x1, y1)    
(x2, y2)    
:       : (1, 10)  (3, 20)
 x = 2   y-    
    : y = 10 + ((2 - 1) / (3 - 1)) * (20 - 10) y = 10 + (1/2) * 10 y = 10 + 5 y = 15
 , x = 2      y- 15 
 :       : y ^ 20 | * (3,20) | / 15 | * (2,15) <-- 
  | / 10 | * (1,10) | +---+---+---+---> x 1 2 3
      ,        
   :
     
   
10
2
        
    :
         ,     
     -  
 -     
  :
        ,       ,  
    :
1.  :      -      
            
       
2.  :          
                

3.  :              
               
4.     :        
         
5.   :          
 ,                  
              
       ,        
     
.       
,         :        
3x² + 6x - 45 = 0    
  ,           ,  -   
               x-    ,
      
       :
1.   (x0  x1)        
11
2
2.        
3.     x-   
4.             , x0  x1     
      
5.               
      : 3x² + 6x - 45 = 0
1:    x0 = 3  x1 = 4   
f(x0) = f(3) = 3(3)² + 6(3) - 45 = 27 + 18 - 45 = 0 f(x1) = f(4) = 3(4)² + 6(4) - 45 = 48 + 24 - 45 =
27
!  f(x0)  f(x1)          
:
x0 = 2: f(2) = 3(2)² + 6(2) - 45 = 12 + 12 - 45 = -21 () x1 = 4: f(4) = 3(4)² + 6(4) - 45 =
48 + 24 - 45 = 27 ()
 !     
 2:     
    :x2 = x0 - (f(x0) * (x1 - x0)) / (f(x1) - f(x0))
    :x2 = 2 - (-21 * (4 - 2)) / (27 - (-21)) = 2 - (-42) / 48 = 2 + 0.875 =
2.875
 3:f(x2)    f(2.875) = 3(2.875)² + 6(2.875) - 45 ≈ 24.796875 + 17.25 - 45 ≈ -
2.953125 ()
 4:    f(2.875)  , f(2)  ,  x0 2.875 
  :  : [2.875, 4]
 5:     :
 2:x2 = 2.875 - (f(2.875) * (4 - 2.875)) / (f(4) - f(2.875)) ≈ 3.0352
f(3.0352) ≈ 0.3199 ()
 : [2.875, 3.0352]
 3: x2 ≈ 3.0004
f(3.0004) ≈ 0.0036 ()
 : [2.875, 3.0004]
 4: x2 ≈ 3.0000
12
2
(3.0000) ≈ 0.0000
    ! 3x² + 6x - 45 = 0   x ≈ 3.0000
  : 3(3)² + 6(3) - 45 = 27 + 18 - 45 = 0
 , x = 3     
     :
                , 
                 

     :                 ,
                  
                 
    :
1.              
2.            
3.         (   )
 :
1.             
2.              
3.           -   
 ,         -    
        ,      
       ,         
      
              
           , 
               -
            
 ,     ,         
               
  ,                 
            
13
2
-
3. (a)             - 
?      
() -    :






󰇛

󰇜
:       :
      ,         
       :
)  :                
        
)  :                
  ,         
)   :               
         
2.        :
             
  :
)  :               
              
       
:         : x + y = 5 2x - y = 1
1:   y x     : y = 5 - x
 :     : 2x - (5 - x) = 1
 3:x    : 2x - 5 + x = 1 3x = 6 x = 2
 4:y = 5 - x  x = 2   y  : y = 5 - 2 = 3
: (x, y) = (2, 3)
14
2
)  :              
                    
   
:         : x + y = 5 2x - y = 1
1: y      : (x + y) + (2x - y) = 5 + 1 3x = 6
 : x    : x = 2
 3:y         x = 2  : 2 + y = 5 y = 3
: (x, y) = (2, 3)
)  :            
           ,     
       
d)  :             
               
    
)   :           
          ,      
   
) - :            
              
   
3. - :
- ,          ,   
           ,   
            
-    :
 1:           2:  
              3:    
   - 
                 
 1:   
              
        
15
2
     :a₁x + b₁y + c₁z = d₁ a₂x + b₂y + c₂z = d₂ a₃x + b₃y + c₃z = d₃
   : [a₁ b₁ c₁ | d₁] [a₂ b₂ c₂ | d₂] [a₃ b₃ c₃ | d₃]
 2:     
       :
     
     ()          
  
            
    ,        :
      
        .
   
   ""   ,   1    
 3: -
      ,             , 
       ,       
,  -          :
  :x + 2y + z = 4 2x + 3y + 2z = 7 3x + 4y + z = 12
 1:   : [1 2 1 | 4] [2 3 2 | 7] [3 4 1 | 12]
 2:     :
a)      x         : R2 = R2 - 2R1 R3 =
R3 - 3R1
[1 2 1 | 4] [0 -1 0 | -1] [0 -2 -2 | 0]
b)     y    
    : R3 = R3 - 2R2
[1 2 1 | 4] [0 -1 0 | -1] [0 0 -2 | 2]
       
 3: x, y  z       - :
  : -2z = 2 z = -1
16
2
  : -y + 0(-1) = -1 y = 1
  : x + 2(1) + 1(-1) = 4 x + 2 - 1 = 4 x = 3
,  : x = 3 y = 1 z = -1
            :
1(3) + 2(1) + 1(-1) = 4 2(3) + 3(1) + 2(-1) = 7 3(3) + 4(1) + 1(-1) ) = 12
-         :
1.  :  --        
       ,       
  
2.    ,           
  
3.            
,        
4.    :            
  
5.             
   
,     :
1.  : ,      , -  
 ,           
2. :   ,        ( )
           
3.    :         
     ,       
      , -        :
1. -  ,           
   ,   1         
2.  :          
  ,          
      
17
2
3.  : ,    ,    - 
 ,           
 , -          
            
  ,          , 
             -  
  ,          
-    ,       ,    
                 
            
   
   -      ,      
   ,        
                
    
-           ,   
           
            ,  
                 
  
4. ()              
()        :
󰇛

󰇜


󰇛

󰇜

󰇛

󰇜
:;  :   
               
                
            :
18
2
1.          ,  
             
                 
  , 2x + 3y = 7 , x  y    
2.    :           
      ,        
  : 2x + 3y = 7 4x - y = 1
   (x  y)      
3.   :         
              
  ,            
: [2 3] [x] = [7] [4 -1] [y] [1]
,       ,   ,    
4.     :  1:       
       (     ),     
            2:   
    A   A^(-1)      ,   A 
   ,             ,
    ,         3: 
                
      4:        

5.     :       
 : 2x + 3y = 7 4x - y = 1
1:     [2 3] [x] = [7] [4 -1] [y] [1]
        A = [2 3] [4 -1] 
  A^(-1) = [-1/10 3/10] [ 4/10 2/10] 
 3:   A^(-1)    A^(-1) * A * [x] = A^(-1) * [7] [y] [1]
 4:  [x] = [-1/10 3/10] * [7] = [1] [y] [ 4/10 2/10] [1] [2]
, x = 1  y = 2.
6.     :
              

19
2
            
              
7.  :
   (-)   
    ,         
         ,  -   
,        ()         
 : - 
-               
                 
               
        
1. -   :-        
              
 ,                
    
-   : 1:       
     (    x1,   x2, )   
          
 :            , 
       
 3:              , 
           
 4:            2      
                  
    
 5:     4           
         ,      
 
2. -   :
     
20
2
             
         
4.  :
        
     -  
         
,  -            :
x₁ + x₂ - x₃ = -2 x₁ + 3x₂ + 2x₃ = 11 x₁ + 3x₂ + x₃ = -4
 1:              ,
   x₁   1      :
x₁ + x₂ - x₃ = -2 ( 1) x₁ + 3x₂ + 2x₃ = 11 ( 2) x₁ + 3x₂ + x₃ = -4 ( 3)
 2:          1 : x₁ = -2 - x₂ + x₃  2 : x₂
= (11 - x₁ - 2x₃) / 3  3 : x₃ = -4 - x₁ - 3x₂
 3:    x₁ = 0, x₂ = 0,  x₃ = 0   
 4:         :
 1:x₁ = -2 - 0 + 0 = -2 x₂ = (11 - (-2) - 2(0)) / 3 = 13/3 ≈ 4.33 x₃ = -4 - (-2) - 3(4.33) = -15
 2:x₁ = -2 - 4.33 + (-15) = -21.33 x₂ = (11 - (-21.33) - 2(-15)) / 3 = 20.78 x₃ = -4 - (-
21.33) - 3(20.78) = -45.01
 3: x₁ = -2 - 20.78 + (-45.01) = -67.79 x₂ = (11 - (-67.79) - 2(-45.01)) / 3 = 56.27 x₃ = -4
- (-67.79) - 3(56.27) = -104.02
      ,         -
             ,  -
             
5.   : -    ,    
  :
) :            ω ()
      - ()      
  :
x_new = ωx_calculated + (1-ω)x_old
 ω  0  2      ω > 1   -   ,  ω < 1 
 -  
21
2
)     -,       
  
) :         -   

d)       -,      
    
    ω = 0.5   -     :
 1: x₁_calc = -2 - 0 + 0 = -2 x₁_new = 0.5(-2) + 0.5(0) = -1
x₂_calc = (11 - (-1) - 2(0)) / 3 = 4 x₂_new = 0.5(4) + 0.5(0) = 2
x₃_calc = -4 - (-1) - 3(2) = -9 x₃_new = 0.5(-9) + 0.5(0) = -4.5
 2:x₁_calc = -2 - 2 + (-4.5) = -8.5 x₁_new = 0.5(-8.5) + 0.5(-1) = -4.75
x₂_calc = (11 - (-4.75) - 2(-4.5)) / 3 = 8.25 x₂_new = 0.5(8.25) + 0.5(2) = 5.125
x₃_calc = -4 - (-4.75) - 3(5.125) = -14.625 x₃_new = 0.5(-14.625) + 0.5(-4.5) = -9.5625
    -   ,    -   
   - ,     ,        
 
6.  :       -     
  ,          ,   
:
1:    [1 1 -1 | -2] [1 3 2 | 11] [1 3 1 | -4]
 2:      R2 = R2 - R1         
: [1 1 -1 | -2] [0 2 3 | 13] [1 3 1 | -4]
3 = 3 - 1: [1 1 -1 | -2] [0 2 3 | 13] [0 2 2 | -2]
3 = 3 - 2: [1 1 -1 | -2] [0 2 3 | 13] [0 0 -1 | -15]
 3:     -    : x₃ = 15   : 2x₂ + 3(15) =
13 2x₂ = 13 - 45 = -32 x₂ = -16   : x₁ + (-16) - 15 = -2 x₁ = -2 + 16 + 15 = 29
,  x₁ = 29, x₂ = -16,  x₃ = 15 
7.   :        
 :
 1: 29 + (-16) - 15 = -2 ()  2: 29 + 3(-16) + 2(15) = 11 ()  3:
29 + 3(-16) + 15 = -4 ()
22
2
     ,         
8.   :       :  - 
         ,      
        ,     
      
           :
   ( 1000  )  ,    
       
,     (      ),   
 
              (   
               ), - 
       
 ,  -          
  ,             
      ,         
       ,       
            
 ,     ,      ,   
        -       
 ,            
               
23
2
-
5. (a)             ?
   
(b)  (X = 0) Y           

-1
-2
2
4
-1
-9
11
69
: 
         :
                 
                
          ,       
                 
 

   ,      
   :
1.             
   
2.         ,    
           
3.  :         ,  
    
4. :           
             
                 ,
                 
 ,       
24
2
2.    
,                
               
        :
a)     )    
         
2a.    
                   
                    
   ,    :
1:      ,       (
 x)             x-     
 :           y-       
     :
   : Δy = y₁ - y₀, y₂ - y₁, y₃ - y₂, ...
  : Δ²y = Δy₁ - Δy₀, Δy₂ - Δy₁, ...
  : Δ³y = Δ²y₁ - Δ²y₀, ...
                 
 3:         :
y = y₀ + p(Δy₀) +(-1)/2!+(-1)(-2)/3!+ ...
:
y₀     y- 
p = (x - x₀) / h,  x           , x₀  x- ,
 h x-      
Δy₀, Δ²y₀, Δ³y₀, ,  2       
 4:                y   

2b.   
         ,        
                :
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2
1:         (x)      
,      x-       
 :                :
  : y = y- yₙ₋₁, yₙ₋₁ - yₙ₋₂, ...
  : ²y = yₙ - yₙ₋₁, yₙ₋₁ - yₙ₋₂, ...
  : ³y = ²yₙ - ²yₙ₋₁, ...
                 
 3:            :
y = yₙ + p(yₙ) +(+1)/2!+(+1)(+2)/3!+ ...
:
yₙ      y- 
p = (x - xₙ) / h,  x           , xₙ  x- ,
 h x-     
󰳛²󰳛³󰳛, ,  2       
 4:                y   

    :
1. :              
  
2. :     ,        
3.           
4.  :               
 
     :
1. :-      
2.  :  ,       
   
3. :  -  ,          
  (         )
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2
4.   
,                
 ,    ,          
        -       
                     , 
               
        :
1:        (x, y)  ,    
 L(x)   :
Lᵢ(x) = ∏(j≠i) (x - xⱼ) / (xᵢ - xⱼ)
       x = x     1        x   xⱼ 
     0  
 :         P(x)  y-      
        :
P(x) = ∑(i=0  n) y * L(x)
 3:           x-  
 
,         :
:        X = 0 , Y  ,   :
 | -1 | -2 | 2 | 4  | -1 | -9 | 11 | 69
1:    
L₁(x) = [(x+2)(x-2)(x-4)] / [(-1+2)(-1-2)(-1-4)] = (x+2)(x-2)(x-4) / 15
L₂(x) = [(x+1)(x-2)(x-4)] / [(-2+1)(-2-2)(-2-4)] = (x+1)(x-2)(x-4) / -24
L₃(x) = [(x+1)(x+2)(x-4)] / [(2+1)(2+2)(2-4)] = (x+1)(x+2)(x-4) / 24
L₄(x) = [(x+1)(x+2)(x-2)] / [(4+1)(4+2)(4-2)] = (x+1)(x+2)(x-2) / 90
 2:     
(x) = -1 * L₁(x) + (-9) * L₂(x) + 11 * L₃(x) + 69 * L₄(x)
 3: x = 0      
(0) = -1 * [2(-2)(-4) / 15] + (-9) * [1(-2)(-4) / -24] + 11 * [1(2)(-4) / 24] + 69 * [1(2)(-2) / 90] =
-1 * (16/15) + (-9) * (8/24) + 11 * (-8/24) + 69 * (-4/90) = -16/15 - 3 - 11/3 - 46/15 = -16/15 -
45/15 - 55/15 - 46/15 = -162/15 = -10.8
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2
,  X = 0, Y ≈ -10.8.
        ,       ,  X 0 ,
Y-  -10.8     
4.      
               ,  
 :
1. :
              
,              
              
 
2.  :
         ,     
             
          
3.   :
  ,      ,   
     
      ,     
4. :
             
          

 - -      ,  
       (  )
5.  :
              
    
           
  
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6.  :
          
        
7.    
          ,  -
    :
1.   :     ,    
           ,   
     ,        
       
2.  :3D           3D  
           
3.   :  -       (, 
 ),             
   
4.  : ,            
       ,         
5.    ():      
          ,     
 
6.  :     2   3  
         
7.             
           
8.  :  ,       
       
9.     
        ,      ?  -
   :
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2
1. 
:
       ,      
  
     ,        
  
2.   :
        ,         

   ,         
      
3.  :
        ,    
    
,    ,      
4.  :
          ,   
      
5.   :
            ,
-             
   -       
6.  :
     ,      
      
7.   :
-,             
   ,       
     
30
2
8. 
          ,     
               :  
  (     )    
                  , 
                 
       
 ,               
                 
 ,            
                
        (     )    
        ,      ,
     
 ,       ,       
               
 ,              
                
-                 ,
                
 -              
         
31
2
6.(a)             
  ? 
()        1/3      :
󰆚
󰇡
󰇢

:     :
()     
              
        ""        
           
        :
1.    :  ,      , 
        a  b    f(x) 
  ,     n    
2.     :           
  f(x0), f(x1), f(x2), ..., f(xn)  ,  x0 = a  xn = b.
3.    :   ,      
          ,  
  
4.   :             
       
    :
∫_a^bf(x) dx ≈ (ba)/2n * [f(x0) + 2f(x1) + 2f(x2) + ... + 2f(xn-1) + f(xn)]
:
a  b    
n    
x0, x1, ..., xn           
    :
(ba)/n     
  1/2               
32
2
      ,    (f(x1)  f(xn-1))   
         
             -  
             ,   
   :        ,     
 
                   
      (       ),  
 4      
,    1/3    :
()   1/3 
  1/3         ,     
                
 ,      
  1/3      :
1.    :   ,   [a,b]   
  ,   1/3   ,     
        2n      
2.     :         : f(x0), f(x1),
f(x2), ..., f(x2n)
3.     1/3    :
∫_a^bf(x) dx ≈ (ba)/6n * [f(x0) + 4f(x1) + 2f(x2) + 4f(x3) + 2f(x4) + ... + 4f(x2n-1) + f(x2n)]
:
a  b    
n       ( 2n  )
x0, x1, ..., x2n           
   :
(ba)/2n     
          1/3    
33
2
     :    1     ,   
  4     ,       (  )
2     
                  
      4:2:4       
  1/3            ,   
                
   ,       -        
      
,           1/3   :
∫_0^(π/2) √( x) dx
1:         6  (n = 3)   

 :     h = (π/2 - 0) / 6 = π/12
 3: x    x0 = 0 x1 = π/12 x2 = π/6 x3 = π/4 x4 = π/3 x5 = 5π/12 x6 = π/2
 4:      f(x) = √(sin x)
f(x0) = √(sin 0) = 0 f(x1) = √(sin(π/12)) ≈ 0.4555 f(x2) = √(sin(π/6)) ≈ 0.6366 f(x3) = √ (sin(π/4))
≈ 0.7654 f(x4) = √(sin(π/3)) ≈ 0.8660 f(x5) = √(sin(5π/12)) ≈ 0.9415 f(x6) = √(sin (π/2)) = 1
 5:   1/3    
∫_0^(π/2) √(sin x) dx ≈ (π/2 - 0)/(6*3) * [f(x0) + 4f(x1) + 2f(x2) + 4f(x3) + 2f(x4) + 4f(x5) +
f(x6)]
≈ (π/18) * [0 + 4(0.4555) + 2(0.6366) + 4(0.7654) + 2(0.8660) + 4(0.9415) + 1]
≈ (π/18) * [0 + 1.8220 + 1.2732 + 3.0616 + 1.7320 + 3.7660 + 1]
≈ (π/18) * 12.6548
≈ 1.1781
,   1/3       6     ∫_0^(π/2)
√(sin x) dx     1.1781 
        ,  1.1803     
      
             ,    
     :
1.  x = 0  √(sin x) 0     ,  sin(0) = 0.
34
2
2. - x 0  π/2   , sin(x) 0  1   ,  √(sin x)   ,
  - (  )
3.  0  π/2       
4.     0  1     ,   π/2 ( 1.57)   ,
       π/2    ,   
5.     1   ,            ,
   1    
       ,       
  ,   6   100    ,     
   
              
  ,          ,  
         ,   (   
)         ,       

     ,      
  :
1.  ,          ,   
           
2.  ,             -
     
3.  ,              ,
 -     
4.  ,              
       
     (     )    
             
      ,               
      
 ,          ,      
-          -     
      ,   -         -
   ,            
35
2
          (     
)     ,     (    
    )          ,    
       ,          
         
   ,          
              
                 
  ,                
  ,    -          
 
            :  
                
     ,  ,       
   
           , 
,               
             
7. ()        
(b)      ?      ?   
:

10
20
30
40
50
60
80

32
20
25
35
40
28
45
: :    
                 
    :
1.  )
2. 
36
2
3. 
       :
1.  ):       ""      
   ,            
 ,    
  ,        : 80, 85, 90, 95, 100
    : a)    : 80 + 85 + 90 + 95 + 100 = 450 b)  
  : 5 c)      : 450 ÷ 5 = 90
    90
              ,  
 ()             
2. :              ,
             ,   
          ,      
      : 80, 85, 90, 95, 100
      ,  5  () ,      : 90.
       ,   98,        : 80,
85, 90, 95, 98, 100
     : 90  95.     ,   
 : (90 + 95) ÷ 2 = 92.5
                  
            ,    
      
3. :                
       ,            
 ,       
      : 2, 3, 3, 4, 4, 4, 5, 5
  , 4    ,        4 
    (        )    
        
37
2
        " "      :
     ,           
     ,            
   
      ,            
      
 ,                
   ,             ,
            
 : 
                
  ,               
  -1  +1     :
+1               -
  ,      
-1            -   ,
    
 0            
  +1  -1     ,         
  :
         +0.8 ,     
-   ,     
        +0.7   ,     
       
      -0.6   ,      -
  ,    
         -     
  ,               
  ,      
38
2
  :
       ,       
    --    :
1. X   Y    -  
2.  (X,Y)    : a) (X - X  )  (Y - Y  )    b) 
   c)     
3.  2b     2c         
4.    : r = Σ((X - Xmean)(Y - Ymean)) / sqrt(Σ(X - Xmean)² * Σ(Y -
Ymean)²)
: r =   X =  X   Y =  Y   Xmean = X    Ymean = Y
   Σ = sqrt    = 
,            :
 (X): 10, 20, 30, 40, 50, 60, 70, 80  (Y): 32, 20, 25, 35, 40, 28, 38, 45
 1:     X   ( ) = (10 + 20 + 30 + 40 + 50 + 60 + 70 + 80) / 8 = 45
Y   () = (32 + 20 + 25 + 35 + 40 + 28 + 38 + 45) / 8 = 32.875

x-x
y-y
x-x
y-y
x-x
x-
)2
y-
y)2
10
32
-35
-0.875
30.625
1225
0.765625
20
20
-25
-
12.875
321.875
625
165.765625
30
25
-15
-7.875
118.125
225
62.015625
40
35
-5
2.125
-10.625
25
4.515625
50
40
5
7.125
35.625
25
50.765625
60
28
15
-4.875
-73.125
225
23.765625
70
38
25
5.125
128.125
625
26.265625
80
35
35
12.125
424.375
1225
147.015625
 2:      
 3:        
39
2
Σ((X - Xmean)(Y - Ymean)) = 975 Σ(X - Xmean)² = 4200 Σ(Y - Ymean)² = 480.875
 4:    
 = 975 /  (4200 * 480.875) = 975 /  (2019675) = 975 / 1421.15 = 0.686
 ,            0.686
  :
0.686               
      ,   , -   ,   
,    ( 1    )
           ,       
        ,       - 
 -      ,   ( , , , ) 
      

   ,        :
1.   :          ,
           
2.               
       
3.     :   ,    
            
   ,       
4.  : ,          
          
5.               
   
,              
          :
1. -  :     ,    - 
              
  ,       
2.  :          
  -           
40
2
3.             
,        
4.              , 
       
5.  :          
  
          ,      
       :
1.              
        
2.  :            
     
3. -         ( 
)      ,      

4.  :         ,   
        
      (,   )      
              , 
     ""    ,       
                , 
       
            ,     -
   ,             
               , 
               
    
41
2
8. (a)   ?             
()                  :

1993
1994
1995
1996
1997
1998

7
10
12
14
17
24
:  :   
                
                  
       ,         
           
    :
1.  :            :
   (  X      )     (  Y
     )          
 
   :              
  (X)     (Y)      
X (  )
Y ( )
2
65
3
70
4
80
5
85
6
90
  ,                
                  :
42
2
 = + 
: Y      X        a Y-   (
      ) b   (       
  )
2.  :          
                 
              

   :        ,  
    (X1)      (X2)       
   
X1 (  )
X2 (  )
Y ( )
2
10
65
3
15
70
4
20
80
5
25
85
6
30
90
  ,     :
 = + 1X1 + 2X2
: Y      X1         X2    
    a Y-   b1       b2   
  
 :
1.   :
o             
43
2
o             
2. :
o          ,   -
       
o -   ,   -    
  
3. :
o              
o -    ,      
4.  :
o -          
         
o          ,  
  
5.   :
o             
o -             
           
6. :
o   : Y = a + bX
o   : Y = a + b1X1 + b2X2 + ... + bnXn
7. :
o    --    
    
o -            
   ,  ,    

             
           ,  -
,         
44
2
 :      
,                    
                
         
  :


1993
7
1994
10
1995
12
1996
14
1997
17
1998
24
 1: 1993, 1994, 1995, 1996, 1997, 1998    1, 2, 3, 4, 5, 6     
          
 ()
 ()
1
7
2
10
3
12
4
14
5
17
6
24
 2:          :
ΣX (X    )
ΣY (Y    )
45
2
ΣXY (X  Y     )
ΣX² ( X    )
n (   )
ΣX = 1 + 2 + 3 + 4 + 5 + 6 = 21
ΣY = 7 + 10 + 12 + 14 + 17 + 24 = 84
ΣXY = (1×7) + (2×10) + (3×12) + (4×14) + (5×17) + (6×24) = 371 ΣX² = 1² + 2² + 3² + 4² + 5² + 6²
= 91
 = 6
 3: (b)  y-  (a)            :
 = ( × ΣXY - ΣX × ΣY) / ( × ΣX² - (ΣX)²)
= (ΣY -  × ΣX) / 
    :
 = (6 × 371 - 21 × 84) / (6 × 91 - 21²) = (2226 - 1764) / (546 - 441) = 462 / 105 = 4.4
= (84 - 4.4 × 21) / 6 = (84 - 92.4) / 6 = -8.4 / 6 = -1.4
 4:      :
 = +   = -1.4 + 4.4X
 X    (1993   1, 1994   2, )  Y  
 5:    :
 Y = -1.4 + 4.4X           :
1.  (b = 4.4)    1993  1998       4.4  
 
2.    y-  (a = -1.4)       ,   " 0"
(       )       
3.                  
        :
o 1993   (X = 1): Y = -1.4 + 4.4(1) = 3
o 1998   (X = 6): Y = -1.4 + 4.4(6) = 25
4.                 , 
              :
o 1999   (X = 7): Y = -1.4 + 4.4(7) = 29.4
46
2
5.              
          ,   
  
              ,    
               :



 
1993
7
3.0
1994
10
7.4
1995
12
11.8
1996
14
16.2
1997
17
20.6
1998
24
25.0
    ,         ,  
               
     :
1.              
2.              
3.  :             
   ,    
     :
1.   :        ,  
      
2.            
 ,       
47
2
3.   :         
    ,   ,  ,    

      ,     :
1.   -   ,        ,
  
2.        ,     
   
3.  (     )      
       
4.             
 ,  ,    ,       
               
 ,            ,    
               
   ,          
          
 ,        ,     
            ,  , 
             ,
              ,    
               
:             ( )       
          ,             