Методичка по Информатике Ч_3
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. 26.1.
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. 26.1
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(26.1) , - -:
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(26.1) |
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(26.3) |
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(26.3), |
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(26.3) |
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J 1 x . |
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X k 1 X k |
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k 1, 2, ..., n , |
(26.7) |
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X k 1 |
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f X k . |
(26.8) |
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.
. 26.2 -
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MINV MPRD -
. MINV -
, MPRD
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1. .
43
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(26.5) |
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(26.7) |
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|X (k) X (k+1)| |
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(26.4) |
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. 26.2 |
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2. |
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26.1) |
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3. |
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. 26.2), |
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5. .
6. -
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44
. 14 -
, 5
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9. - .
: [3, 4, 7] .
27
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y x0 |
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(27.1) |
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. 27.1 |
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yi xi x0 ih :
yi yi 1 hf xi 1, yi 1 . |
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M 0 x0 , y0 , M1 x1, y1 , , M n xn , yn ( |
. 27.1). |
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1
dy
dx
3x y
x0 0,0 , xk 1,2 , h 0,05 , y0 1,0 .
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C
READ(5,*) X0, XK, H, Y0
C N
ZN=(XK-X0)/H
N=ZN
Y=Y0
X=X0
WRITE(5,*) X,Y
C
DO 1 I=1, N
FY=F(X, Y)
Y=Y+H*FY
X=X0+H*I
1WRITE(5,*) X,Y STOP
END
48
C FUNCTION F(X1, Y1)
F=3*X1+Y1 RETURN END
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k4 f xi h; yi hk3;
i 0, 1, 2, 3, ... .
yi 1 |
xi h . |
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(27.11) |
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(27.1) |
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49 |
~
y x, h , (27.11)
h .
x , 0,5h ,
yx, 0,5h. - -.
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y x, h |
y x, 0,5h |
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(27.12) |
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R
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2
( 27.1) - - .
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C -
READ(5,*) X0, XK, H, Y0
C N
ZN=(XK-X0)/H
N=ZN
C
Y=Y0
X=X0
WRITE(5,*) X, Y
C
DO 1 I=1, N
CALL DIF(H, X, Y)
X=X0+H*I
1WRITE(5,*) X, Y STOP
END
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