: .
:
I y /= f (x,y) .
1. given (), .
2. , Evaluation ().
3. , .
4. Odesolve, , , , Odesolve .
5. , .
6. .
II rkfixed.
1. , .
2. , Evaluation ().
3. .
4. , , rkfixed : , , , .
5. , .
6. .
8.1 8
f(x,y) | ||||
y(1)=1 | [1,10] | |||
tg(x)t(y) | y(0)=0 | [0,5] | 0.5 | |
y(1)=1 | [1,7] | |||
y(1)=1 | [1, 5] | 0.25 | ||
cos(x-2y)-cos(x+2y) | y(0)=p/4 | [0,4p] | p/2 | |
2e-xcos(x)-y | y(0)=0 | [0;3,5] | 0,1 | |
e-2ycos(x)-y | y(0)=0 | [0;1] | 0,05 | |
lnôx+2,5xsin(x)ô | y(0)=2,5 | [1;3,5] | 0,2 | |
e35ysin(x)+y | y(0)=0 | [0;1,5] | 0,1 | |
x2ln(x+y2) | y(0)=3,5 | [1,2;2,4] | 0,08 | |
y(0)=3,6 | [4,1;6,7] | 0,1 | ||
sin(x)+cos(y2) | y(0)=2,2 | [0,8;3,2] | 0,1 | |
e-2xsin(x+y) | y(0)=16,2 | [4,8;6,4] | 0,1 | |
0,7y+x×ln(x+y) | y(0)=2,5 | [12,4;14,1] | 0,08 |
0,5x+ye(x-y) | y(0)=3,1 | [8,5;9,7 ] | 0,05 | |
x2+ycos(x) | y(0)=1,4 | [0;2,3] | 0,1 | |
y2-exy | y(0)=1,7 | [2,4;3,5] | 0,05 | |
xy-e(x-y) | y(0)=2,8 | [1,6;3,1] | 0,1 | |
sin(xy)-e2x | y(0)=5,7 | [14,5;16,3] | 0,05 | |
y(0)=1,6 | [5,2;6,8] | 0,1 | ||
y/ln(y) | y(2)=1 | [2;5] | 0,25 | |
e(x+y)-e(x-y) | y(0)=0 | [0;2.5] | 0,1 | |
y(p/4)=0 | [p/4, 3p] | p/8 | ||
y(1)=0 | [1;4] | 0.3 | ||
sin(3x)-y×tg(3x) | y(0)=1/3 | [0,4] | 0,25 | |
cos(x-4y)-cos(x+4y) | y(0)=p/4 | [0,4p] | p/2 | |
2e-xcos(x)y | y(0)=0 | [0;3,5] | 0,1 | |
e-2ycos(x)+y | y(0)=0 | [0;1] | 0,05 | |
lnôx+sin(x)ô | y(0)=2,5 | [1,5;3,5] | 0,2 | |
ey+2sin(x) | y(0)=0 | [0;1,5] | 0,1 |
|
|
I [0,100]. : (0)=1.
1 Given.
2 , , :
.
3 , :
(0)=1.
4 Odesolve:
:=Odesolve(t,100).
5 t:=0,..10
t:=0,..10.
6 .
26-
II rkfixed.
1.
(0):=0.1.
2. .
3. :=100.
4. rkfixed. ().
=rkfixed(, 1,2,, D).
5. :=0,..100
:=0,..100.
6. .
. |
: . : Bulstoer, Rkadapt. rkfixed, :
,
.
1. ?
2. ?
3. ?