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《常微分方程——解析方法与数值方法》PPT 第5章
2022-10-25 | 阅:  转:  |  分享 
  
15ù

?5~???§|)??{

N¢?4?[

wg??

06/01/2022

N¢?4?[ (wg??) 15ù 06/01/2022 1 / 92

81

1 ?5???§|??n?

?Vg

3??5?n

àg?5???§|

?àg?5???§|

2 ~Xê?5???§|

Y


?)Y
O?

3 A^ˉKT~

N¢?4?[ (wg??) 15ù 06/01/2022 2 / 92

81

1 ?5???§|??n?

?Vg

3??5?n

àg?5???§|

?àg?5???§|

2 ~Xê?5???§|

Y


?)Y
O?

3 A^ˉKT~

N¢?4?[ (wg??) 15ù 06/01/2022 3 / 92

?Vg

??n??ê?tx(t)?

x(t) =

26

6666

6666

6664

x1(t)

x2(t):

::

xn(t)

37

7777

7777

7775; ?xT(t) = [x1(t);x2(t); ;xn(t)]; (1.1)

ùpxT(t)L?x(t)=?,ù¥z???txi(t)(i = 1;2; ;n)??

ma6t6bt?Y?ê.

??n n?êY
A(t)?

A(t) =

26

6666

6666

6664

a11(t) a12(t) a1n(t)

a21(t) a22(t) a2n(t):

:: ::: :::

an1(t) an2(t) ann(t)

37

7777

7777

7775; (1.2)

§z???aij(t)(i;j = 1;2; ;n)??ma6t6bt?Y?ê.

N¢?4?[ (wg??) 15ù 06/01/2022 4 / 92

??

?Y: ?tx(t)??Y
A(t)z????3?ma6t6bt?Y,K?

T?t??Y
3?ma6t6bt′?Y.

??: ?tx(t)??Y
A(t)z????3?ma6t6bt??,K?

T?t??Y
3?ma6t6bt′??,?k

x0(t) =

26

6666

6666

6666

664

x01(t)

x02(t)

:::

x0n(t)

37

7777

7777

7777

775

; (1.3)

A0(t) =

26

6666

6666

6666

664

a011(t) a012(t) a01n(t)

a021(t) a022(t) a02n(t)

::: ::: :::

a0n1(t) a0n2(t) a0nn(t)

37

7777

7777

7777

775

:

N¢?4?[ (wg??) 15ù 06/01/2022 5 / 92

e??óY
A(t);B(t)9ó??tx(t);y(t)t3?ma6t6bt??,

Kk

[A(t) + B(t)]0 = A0(t) + B0(t);

[x(t) + y(t)]0 = x0(t) + y0(t);

[A(t)B(t)]0 = A0(t)B(t) + A(t)B0(t);

[A(t)x(t)]0 = A0(t)x(t) + A(t)x0(t):

??

?è: ?tx(t)??Y
A(t)z????3?ma6t6bt?è,K?

T?t??Y
3?ma6t6bt′?è,?k

N¢?4?[ (wg??) 15ù 06/01/2022 6 / 92

Z b

a

A(t)dt =

26

6666

6666

6666

6666

6666

6666

6666

4

R b

a a11(t)dt

R b

a a12(t)dt

R b

a a1n(t)dt

R b

a a21(t)dt

R b

a a22(t)dt

R b

a a2n(t)dt

::: ::: :::

R b

a an1(t)dt

R b

a an2(t)dt

R b

a ann(t)dt

37

7777

7777

7777

7777

7777

7777

7777

5

;

Z b

a

x(t)dt =

26

6666

6666

6666

6666

6666

6666

6664

R b

a x1(t)dt

R b

a x2(t)dt

:::

R b

a xn(t)dt

37

7777

7777

7777

7777

7777

7777

7775

:

N¢?4?[ (wg??) 15ù 06/01/2022 7 / 92

??

n??tx = (x1;x2; ;xn)T?ê?

kxk=

nX

i=1

jxij;

n nY
A?ê?

kAk=

nX

i=1

jaijj:

??n nY
A =fai;j;i;j = 1;2; ;ng;B =fbi;j;i;j = 1;2; ;ngún?

?tx =fxi;i = 1;2; ;ng;y =fyi;i = 1;2; ;ng,±9?ma6t6bt

?è?êY
ú?ê?tA(t);x(t),Kk

N¢?4?[ (wg??) 15ù 06/01/2022 8 / 92

1.kxk>0?kxk= 0??^?′xi = 0(i = 1;2; ;n);

kAk>0?kAk= 0??^?′aij = 0(i;j = 1;2; ;n);

2.é??~êk,k

kkxk=jkjkxk; kkAk=jkjkAk;

3.kx + yk6kxk+kyk; kA + Bk6kAk+kBk;

4.kAxk6kAkkxk;kABk6kAkkBk;

5.





R b

a x(t)dt



6

R b

a kx(t)kdt;





R b

a A(t)dt



6

R b

a kA(t)kdt; a6b:

N¢?4?[ (wg??) 15ù 06/01/2022 9 / 92

??

e?tSfxkg(xk = (x1k;x2k; ;xnk)T)éz??k(k = 1;2; ;n)?′?

?,K??tSfxkg′???.

??

e?ê?tSfxk(t)g(xk(t) = (x1k(t);x2k(t); ;xnk(t))T)éz??k(k = 1;

2; ;n)3?ma6t6bt?′??(????),K??ê?tS

fxk(t)g′???(????).

??

e?ê?t?êP1k=1 xk(t)ü?ú¤¤?ê?tS3?

ma6t6bt′??(????),K?P1k=1 xk(t)3?ma6t6bt′

??(????).

N¢?4?[ (wg??) 15ù 06/01/2022 10 / 92

?Xe????§|

8>>

>>>>

<>

>>>>

>:

x01(t) = a11(t)x1(t) + a12(t)x2(t) + + a1n(t)xn(t) + f1(t);

x02(t) = a21(t)x1(t) + a22(t)x2(t) + + a2n(t)xn(t) + f2(t);



x0n(t) = an1(t)x1(t) + an2(t)x2(t) + + ann(t)xn(t) + fn(t);

(1.4)

??

?§|(1.4)''ux1;x2; ;xn9x01;x02; ;x0n′?5,
??§|(1.4)

???5?????§|. e?§|¥??êê′9±

t,K?ù?p?????§|.

N¢?4?[ (wg??) 15ù 06/01/2022 11 / 92

e?ê?tu(t)êu0(t)3?m[ ; ] [a;b]t?Y,?÷v

u0(t) = A(t)u(t) + f(t); t2[ ; ] (1.5)

K?u(t)??§|(1.4)3?m[ ; ] [a;b]t??).

XJ??D?^?

x(t0) = ; (1.6)

K÷v^?(1.6)?§|(1.4)|)ˉK??D?ˉK??)ˉK.3

?1t0?m[ ; ] [a;b]S,)u(t)÷v

u(t0) = :

N¢?4?[ (wg??) 15ù 06/01/2022 12 / 92

~

y?ê?t

u(t) =

" sint

cost

#

′D?ˉK

x0(t) =

" 0 1

1 0

#

x(t); x(0) =

" 0

1

#

3?m( 1;+1)t).

): du sint;cost3?m( 1;+1)t?Y?,?\?§

u0(t) =

" sint

cost

#0

=

" cost

sint

#

=

" 0 1

1 0

#" sint

cost

#

=

" 0 1

1 0

#

u(t):


?k

u(0) =

" sin0

cos0

#

=

" 0

1

#

;

?d, u(t)??§D?ˉK).

N¢?4?[ (wg??) 15ù 06/01/2022 13 / 92

??n?5???§D?ˉK(

x(n) + a1(t)x(n 1) + + an 1(t)x0+ an(t)x = f(t);

x(t0) = 1;x0(t0) = 2; ;x(n 1)(t0) = n; (1.7)

?LCtC?

x1(t) = x(t);x2(t) = x01(t); ;xn(t) = x0n 1(t)

òD?ˉK(1.7)z?Xe??5???§|D?ˉK

8>>

>>>>

>>>>

>>><

>>>>

>>>>

>>>>

>:

x0(t) =

26

6666

6666

6666

6666

6666

4

0 1 0 0

0 0 1 0

::: ::: ::: :::

0 0 0 1

an(t) an 1(t) an 2(t) a1(t)

37

7777

7777

7777

7777

7777

5

x(t) +

26

6666

6666

6666

6666

6666

4

0

0

:::

0

f(t)

37

7777

7777

7777

7777

7777

5

;

x(t0) = ;

(1.8)

N¢?4?[ (wg??) 15ù 06/01/2022 14 / 92

ù¥

x(t) =

26

6666

6666

6666

664

x1(t)

x2(t)

:::

xn(t)

37

7777

7777

7777

775

=

26

6666

6666

6666

664

x(t)

x0(t)

:::

x(n 1)(t)

37

7777

7777

7777

775

; =

26

6666

6666

6666

664

1

2

:::

n

37

7777

7777

7777

775

:

5:ˉ¢t, n?5???§D?ˉK(5-8)???5???§|

D?ˉK(5-9)3ù??e′d. =??ù¥??D?ˉK),

?E,??D?ˉK).

~

òD?ˉK

x000+ tx00 3t2x0+ 7x = et; x(0) = 1; x0(0) = 0; x00(0) = 1

z???d??5???§|D?ˉK.

N¢?4?[ (wg??) 15ù 06/01/2022 15 / 92

):-

x1(t) = x; x2(t) = x01(t) = x0; x3(t) = x02(t) = x00;

Kk

x =

26

6666

6664

x1(t)

x2(t)

x3(t)

37

7777

7775; x0 =

26

6666

6664

x01(t)

x02(t)

x03(t)

37

7777

7775; =

26

6666

6664

1

0

1

37

7777

7775:

q??

x01(t) = x0 = x2(t);

x02(t) = x00 = x3(t);

x03(t) = x000 = tx00+ 3t2x0 7x + et

= tx3(t) + 3t2x2(t) 7x1(t) + et;

u′

x0 =

26

6666

6664

0 1 0

0 0 1

7 3t2 t

37

7777

7775x +

26

6666

6664

0

0

et

37

7777

7775;

N¢?4?[ (wg??) 15ù 06/01/2022 16 / 92

?k

x(0) =

26

6666

6664

x1(0)

x2(0)

x3(0)

37

7777

7775 = :

I???′: z??n?5???§??z?n???5???§

¤¤?§|,?L5%?¤á. ~X,?§|

x0 =

" 1 0

0 1

#

x; x =

" x

1

x2

#

;

?Uz????5???§.

N¢?4?[ (wg??) 15ù 06/01/2022 17 / 92

3??5?n

?n

XJ?êY
A(t)ú?ê?tf(t)3?m[a;b]t?Y,K??5???

§|D?ˉK (

x0(t) = A(t)x(t) + f(t);

x(t0) = ; t0 2[a;b]; (1.9)

3?m[a;b]S3??)x = x(t).

ún

??5???§|D?ˉK(1.9)3?m[a;b]t?Y)duè?

?§|

x(t) = +

Z t

t0

[A(s)x(s) + f(s)]ds (1.10)

3?m[a;b]t?Y).

N¢?4?[ (wg??) 15ù 06/01/2022 18 / 92

E?kS??ê?tS

8>>

<>

>:

’0(t) = ;

’k(t) = + R tt

0

[A(s)’k 1(s) + f(s)]ds; t2[a;b];k = 1;2; : (1.11)

ùp,?kS??ê?t’k(t)????5???§|D?ˉ

K(1.9)11kgCq).

ún

éu¤kêk,?kS??ê?tSf’k(t)g3?m[a;b]tk??

??Y.

ún

?kS??ê?tSf’k(t)g3?m[a;b]t′????.

N¢?4?[ (wg??) 15ù 06/01/2022 19 / 92

y2: du

’k(t) = ’0(t) +

kX

j=1

[’j(t) ’j 1(t)]; (1.12)

?d?y2?kS??ê?tSf’k(t)g3?m[a;b]t????,?Iy

2a(1.12)mà?ê?ê3?m[a;b]t????=?.

??A(t), f(t)34?m[a;b]t?Y,¤±kA(t)k,kf(t)kt3[a;b]tk.,=

3~êLúK,|

kA(t)k6L; kf(t)k6K; t2[a;b]:

u′k

k’1(t) ’0(t)k=





Z t

t0

[A(s)’0(s) + f(s)]ds





6

Z t

t0

kA(s)’0(s) + f(s)kds

6M(t t0); t06t6b;

ù¥M = Lk k+ K.

N¢?4?[ (wg??) 15ù 06/01/2022 20 / 92

ók

k’2(t) ’1(t)k=

Z t

t0

kA(s)[’1(s) ’0(s)]kds

6L

Z t

t0

k’1(s) ’0(s)kds

6 ML2 (t t0)2; t06t6b:

dê?8B{

k’k(t) ’k 1(t)k6 ML

k 1

k! (t t0)

k6 MLk 1

k! (b t0)

k: (1.13)

d?dA.dO{?,

1P

k=1

MLk 1

k! (b t0)

k3?m[t0;b]t????,

Kk?ê?ê kP

j=1

[’j(t) ’j 1(t)]3?m[t0;b]t????,l
?kS

??ê?tSf’k(t)g3[t0;b]t????.

N¢?4?[ (wg??) 15ù 06/01/2022 21 / 92

ún

’(t)′è??§|(1.10)??3?m[a;b]t?Y),?d,’(t)?′D?

ˉK(1.9)??3?m[a;b]t).

y2:-lim

k!1

’k(t) = ’(t),Kéa(1.11)¥1aüàó?4??

’(t) = lim

k!1

’k(t) = lim

k!1

"

+

Z t

t0

(A(s)’k 1(s) + f(s))ds

#

= +

Z t

t0

lim

k!1

[A(s)’k 1(s) + f(s)]ds

= +

Z t

t0

[A(s)’(s) + f(s)]ds:

(1.14)

N¢?4?[ (wg??) 15ù 06/01/2022 22 / 92

ún

e (t)′è??§|(1.10)??3?m[a;b]t,??),K7

k (t) ’(t), t2[a;b],=è??§|(1.10))′??.

y2: du

(t) = +

Z b

t0

[A(s) (s) + f(s)]ds; (1.15)

a(1.14)?a(1.15)?~?

k’(t) (t)k=





Z t

t0

[A(s)(’(s) (s))]ds





6

Z b

t0

kA(s)kk’(s) (s)kds

6L

Z t

t0

k’(s) (s)kds:

N¢?4?[ (wg??) 15ù 06/01/2022 23 / 92

-

g(t) =k’(t) (t)k; u(t) =

Z t

t0

g(s)ds;

K

g(t)6L

Z t

t0

g(s)ds = Lu(t):


u0(t) = g(t),¤±

u0(t)6Lu(t);

u′

[u0(t) Lu(t)]e Lt60:

üàè?? Z

t

t0

u0(s)e Lsds L

Z t

t0

u(s)e Lsds

= u(s)e Ls





t

t0

= u(t)e Lt u(t0)e Lt0

60;

N¢?4?[ (wg??) 15ù 06/01/2022 24 / 92

Kk

u(t)6u(t0);

= Z t

t0

g(s)ds =

Z t

t0

k’(t) (t)kds60:

?d,k’(t) (t)k= 0,’(t) (t).

d±túnB??ny2.

5:3?y2L§¥,·?uy??5???§|D?ˉK(1.9)

)3?m?XêY
A(t)ú?àg?f(t)?Y?m[a;b].ù?:?

12ù¥''u????§D?ˉK)3??5?n9)

3?m?ó.??3E?k?ú%C?êS¥=IXêY
A(t)ú

?àg?f(t)?Y=?,¤±éu??5???§|D?ˉK(1.9)5

`,?3)ò?.

N¢?4?[ (wg??) 15ù 06/01/2022 25 / 92

í?

XJai(t)(i = 1;2; ;n), f(t)3?m[a;b]t?Y,Ké??t0 2[a;b]9

??~ê i(i = 1;2; ;n),?§

x(n) + a1(t)x(n 1) + + an 1(t)x0+ an(t)x = f(t)

3??3?m[a;b]t??)w(t),?÷vD?^?

w(t0) = 1;w0(t0) = 2; ;w(n 1)(t0) = n:

N¢?4?[ (wg??) 15ù 06/01/2022 26 / 92

àg?5???§|

!·?k5??àg?5???§|

dx(t)

dt = A(t)x(t) (1.16)

?)(,ù¥x(t);A(t)

?n

(U\n) ex1(t);x2(t)′àg?5???§|(1.16)),K§??

5|ü x(t) = c

1x1(t) + c2x2(t) (1.17)

E,′àg?5???§|(1.16)),ù¥c1;c2???~ê.

N¢?4?[ (wg??) 15ù 06/01/2022 27 / 92

y2: du

dx(t)

dt =

d

dt(c1x1(t) + c2x2(t))

= c1dx1(t)dt + c2dx2(t)dt

= c1A(t)x1(t) + c2A(t)x2(t)

= A(t)[c1x1(t) + c2x2(t)]

= A(t)x(t);

y.

-V =fàg?5???§|(1.16)3?m[a;b]t??)g,K?n`2

8üV′???5?m.

ún

8üV′??n??5?m.

N¢?4?[ (wg??) 15ù 06/01/2022 28 / 92

y2:-t0 2[a;b],d)3??5?n?,éu??~ê?

tx0 2Rn,3V¥3???x(t),?÷vx(t0) = x0. l
3N

H : Rn !V;(=òx0Nx(t)):

duéu??x(t)2V,kx(t0)2Rn,?

H(x(t0)) = x(t);

?dNH′÷N. q??éu??x1;x2 2Rn,-

x1(t) = H(x1); x2(t) = H(x2);

d)??5?,

x1(t) , x2(t); t2[a;b]; ?=x1 , x2;

¤±NHq′??N,?dU\nú)??5

H(c1x1 + c2x2) = c1H(x1) + c2H(x2):

?d,NH′?5,?′??lRnVóN.

N¢?4?[ (wg??) 15ù 06/01/2022 29 / 92

ù??XRn?Vk?ó?5(,¤±V′??n??5?m,=àg?

5???§|(1.16))¤?5?m?ê??§|ê?ó.

?n

(?)() eàg?5???§|(1.16)3?m[a;b]tkn??5?''

)

x1(t);x2(t); ;xn(t); (1.18)

K§?)?L??

x(t) = c1x1(t) + c2x2(t) + + cnxn(t);

ù¥ci(i = 1;2; ;n)???~ê.

)|(1.18))¤
)?5?mV,?~?ù?àg?5???§

|(1.16)???)|.?d,|àg?5???§|(1.16)?)?I

|?§???)|=?.

N¢?4?[ (wg??) 15ù 06/01/2022 30 / 92

@o·?I?)?ü?ˉK:

(1)|?àg?5???§|(1.16)n?)x1(t);x2(t); ;xn(t);

(2)y2)|x1(t);x2(t); ;xn(t)?5?''.

??

)|xi(t)(i = 1;2; ;n)?t/a?

xi(t) =

26

6666

6666

6666

664

x1i(t)

x2i(t)

:::

xni(t)

37

7777

7777

7777

775

; i = 1;2; ;n;

K§Kd?1a?

W(t) =











x11(t) x12(t) x1n(t)

x21(t) x22(t) x2n(t)

::: ::: :::

xn1(t) xn2(t) xnn(t)











:

N¢?4?[ (wg??) 15ù 06/01/2022 31 / 92

ún

)|(1.18)Kd?1a÷v4?úa

W(t) = W(t0)e

R t

t0 tr(A(t))dt; x2[a;b]; (1.19)

ù¥, t0 2[a;b]; tr(A(t))L?Y
A(t),,=tr(A(t)) = nP

i=1

aii(t).

y2:

dW(t)

dt =

nX

i=1

















x11(t) x12(t) x1n(t)

x21(t) x22(t) x2n(t)

::: ::: :::

dxi1(t)

dt

dxi2(t)

dt

dxin(t)

dt:

:: ::: :::

xn1(t) xn2(t) xnn(t)

















N¢?4?[ (wg??) 15ù 06/01/2022 32 / 92

=

nX

i=1

















x11(t) x12(t) x1n(t)

x21(t) x22(t) x2n(t)

::: ::: :::

nX

j=1

aijxj1

nX

j=1

aijxj2

nX

j=1

aijxjn

::: ::: :::

xn1(t) xn2(t) xnn(t)

















=

nX

i=1

aii W(t) = tr(A(t)) W(t);

üàè?Ba(1.19).

t?ún`2:)|(1.18)Kd?1aW(t)e3,:t0??",K3

??mt??";e3,:t0???",K3??mt???".

=W(t)?oe?",?oe??".

N¢?4?[ (wg??) 15ù 06/01/2022 33 / 92

?n

àg?5???§|(1.16))|(1.18)?5?''??^?′

W(t) , 0; t2[a;b]:

y2:e)|x1(t);x2(t); ;xn(t)?5?'',=?§|

c1x1(t) + c2x2(t) + + cnxn(t)

=

26

6666

6666

6666

664

x11(t) x12(t) x1n(t)

x21(t) x22(t) x2n(t)

::: ::: :::

xn1(t) xn2(t) xnn(t)

37

7777

7777

7777

775

26

6666

6666

6666

664

c1

c2

:::

cn

37

7777

7777

7777

775

= 0

?k"),¤±XêY
1a÷?,=W(t) , 0;t2[a;b].

N¢?4?[ (wg??) 15ù 06/01/2022 34 / 92

??,eW(t) , 0,dún?,éu,:t0 2[a;b],kW(t0) , 0,=

x1(t0);x2(t0); ;xn(t0)

3Rn¥?5?'',u′k

H(0) = H(c1x1(t0) + c2x2(t0) + + cnxn(t0))

= c1x1(t) + c2x2(t) + + cnxn(t) = 0;

í?

)|x1(t);x2(t); ;xn(t)?5?''.)|(1.18)?5?''??^?



W(t) 0; t2[a;b]:

N¢?4?[ (wg??) 15ù 06/01/2022 35 / 92

~

y x

1

x2

!

= c1

et

0

!

+ c2

tet

et

!

′???§| x0

1x0

2

!

=

1 1

0 1

! x

1

x2

!

(1.20)

?),ù¥c1;c2???~ê.

)μ-

’1(t) =

et

0

!

; ’2(t) =

tet

et

!

:

??

’01(t) =

et

0

!

=

1 1

0 1

! et

0

!

=

1 1

0 1

!

’1(t);

¤±’1(t)′?§|(1.20)).

N¢?4?[ (wg??) 15ù 06/01/2022 36 / 92

q??

’02(t) =

tet

et

!0

=

et + tet

et

!

=

1 1

0 1

! tet

et

!

=

1 1

0 1

!

’2(t)

¤±’2(t)?′?§|(1.20)).


?Det(’1(t);’2(t)) , 0,¤±)’1(t);’2(t)?5?'', c1’1(t) + c2’2(t)?

?§|?).

éu)|x1(t);x2(t); ;xn(t),·???±ò§?¤Y
/a

(t) =

26

6666

6666

6666

664

x11(t) x12(t) x1n(t)

x21(t) x22(t) x2n(t)

::: ::: :::

xn1(t) xn2(t) xnn(t)

37

7777

7777

7777

775

;

(t)??àg?5???§|(1.16)))YY
.

N¢?4?[ (wg??) 15ù 06/01/2022 37 / 92

XJ)|x1(t);x2(t); ;xn(t)?5?'',=′???)|?,·?

? (t)?àg?5???§|(1.16)?))YY
.AO/, (t) = E(E?

óü?Y
)?,?ù?IO?))YY
.

ò)Y
(t)?\àg?5???§|(1.16)?

0(t) = (x0ij(t))n n =

0B

BBBB

B@

nX

k=1

aik(t)xkj(t)

1C

CCCC

CA

n n

= (aij(t))n n(xij(t))n n = A(t) (t);

¤±)Y
(t)?′àg?5???§|(1.16)Y
/a),=Y
).

??,e (t)′àg?5???§|(1.16)Y
),K§z??′

àg?5???§|(1.16)).

N¢?4?[ (wg??) 15ù 06/01/2022 38 / 92

?n

XJ (t)?àg?5???§|(1.16)?)Y
,@oàg?5???

§|(1.16)??)’(t)?L??

’(t) = (t)c;

ùp, c?(?n?~ê?t.

?n

àg?5???§|(1.16))Y
(t)′?)Y
??^?′

(1)1aDet( (t)) , 0; t2[a;b];?

(2)3t0 2[a;b];Det( (t0)) , 0,l
Det( (t)) , 0.

?n

XJ (t)′àg?5???§|(1.16)3?m[a;b]t?)Y
,

C′n n??é~êY
,@o (t)C?′àg?5???§|(1.16)

3?m[a;b]t?)Y
.

N¢?4?[ (wg??) 15ù 06/01/2022 39 / 92

y2:??

( (t)C)0 = 0(t)C = A(t) (t)C = A(t)( (t)C);

¤± (t)C′àg?5???§|(1.16))Y
. q?? (t)′?)Y


, C??é,Kk

Det( (t)C) = Det( (t))Det(C) , 0;

¤±, (t)C′?)Y
.

dt??n?,ü??)Y
?m? ????é~êY
.

í?

e (t); (t)′àg?5???§|(1.16)3?m[a;b]tü??)Y
,

K??3??n n??é~êY
C,|3?m[a;b]t

(t) = (t)C:

N¢?4?[ (wg??) 15ù 06/01/2022 40 / 92

y2:?? (t); (t)′?m[a;b]t?)Y
,¤± 1(t)3,?

U(t) = 1(t) (t)

E,?n nY
,Kk

(t) = (t)U(t);

u′

0(t) = 0(t)U(t) + (t)U0(t)

= A(t) (t)U(t) + (t)U0(t)

= A(t) (t) + (t)U0(t):

du (t)÷vàg?5???§|(1.16),¤±

(t)U0(t) = 0:

u′kU0(t) = 0,U(t) = C?n n~êY
.

N¢?4?[ (wg??) 15ù 06/01/2022 41 / 92

?àg?5???§|

??§|

x0(t) = A(t)x(t) + f(t); (1.21)

T?§|?éAuàg?5???§|(1.16)?àg?5???§|.

5?

e’(t)′?àg?5???§|(1.21)), (t)′?àg?5???§

|(1.21)éAàg?5???§|(1.16)),K’(t) + (t)′?àg?

5???§|(1.21)).

y2: du

’0(t) = A(t)’(t) + f(t);

0(t) = A(t) (t);

òüa?\

(’(t) + (t))0 = A(t)(’(t) + (t)) + f(t);

’(t) + (t)′?àg?5???§|(1.21)).

N¢?4?[ (wg??) 15ù 06/01/2022 42 / 92

5?

e’(t);’(t)′?àg?5???§|(1.21)ü?),K’(t) ’(t)′éA

àg?5???§|(1.16)).

y2: du

’0(t) = A(t)’(t) + f(t);

’0(t) = A(t)’(t) + f(t);

üa?~,

(’(t) ’(t))0 = ’0(t) ’0(t) = A(t)(’(t) ’(t));

’(t) ’(t)′àg?5???§|(1.16)).

?n

e (t)′àg?5???§|(1.16)???)Y
, (t)′?àg?5

???§|(1.21)??A),K?àg?5???§|(1.21)?)?

L??

’(t) = (t)c + (t); (1.22)

ù¥, c?(?~ê?t.

N¢?4?[ (wg??) 15ù 06/01/2022 43 / 92

y2:??

’0(t) = 0(t)c + 0(t)

= A(t) (t)c + A(t) (t)

= A(t)( (t)c + (t))

= A(t)’(t);

¤±’(t)′?àg?5???§|(1.21)).

u′d5??,’(t) (t)′àg?5???§|(1.16)).2d?n

?,3~ê?tc,|

’(t) (t) = (t)c;

u′?n(?.

N¢?4?[ (wg??) 15ù 06/01/2022 44 / 92

e?éu??àg?5???§||),·?a''12ù??àg

?5???§|)§E,?±|^~êC′{,=òéAàg?5?

??§|(1.16)) (t)c¥~ê?tcC?c(t).

b?

’(t) = (t)c(t) (1.23)

??àg?5???§|(1.21)),òù?\?§|

0(t)c(t) + (t)c0(t) = A(t) (t)c(t) + f(t):

du (t)′éAàg?5???§|(1.16)?)Y
,?dta?z

{?

(t)c0(t) = f(t):

3t0ttè??

c(t) = c(t0) +

Z t

t0

1(s)f(s)ds:

da(1.23)?

c(t0) = 1(t0)’(t0);

N¢?4?[ (wg??) 15ù 06/01/2022 45 / 92

u′k

c(t) = 1(t0)’(t0) +

Z t

t0

1(s)f(s)ds:

¤±|

’(t) = (t) 1(t0)’(t0) + (t)

Z t

t0

1(s)f(s)ds: (1.24)

,???,éa(1.24)üà|?

’0(t) = 0(t) 1(t0)’(t0) + 0(t)

Z t

t0

1(s)f(s)ds + (t) 1(t)f(t)

= A(t) (t)[ 1(t0)’(t0) +

Z t

t0

1(s)f(s)ds] + f(t)

= A(t)’(t) + f(t):

?d,?àg?5???§|(1.21)÷vD?^?’(t0) = )?

’(t) = (t) 1(t0) + (t)

Z t

t0

1(s)f(s)ds: (1.25)

N¢?4?[ (wg??) 15ù 06/01/2022 46 / 92

~

|D?ˉK

x0(t) =

" 1 1

0 1

#

x(t) +

" e t

0

#

; x(0) =

" 1

1

#

).

): dc~?

(t) =

" et tet

0 et

#

??§éAàg?5???§|?)Y
,K|^~êC′{ò

(t)c(t) =

" et tet

0 et

#

c(t)

?\?§,?

(t)c0(t) =

" et tet

0 et

#

c0(t) =

" e t

0

#

= f(t):

N¢?4?[ (wg??) 15ù 06/01/2022 47 / 92

du

1(t) =

" et tet

0 et

# 1

= e 2t

" et tet

0 et

#

= e t

" 1 t

0 1

#

;

K

c0(t) = e t

" 1 t

0 1

#" e t

0

#

=

" 1 t

0 1

#" e 2t

0

#

=

" e 2t

0

#

:

üàè?

c(t) = 1(0)

" 1

1

#

+

Z t

0

" e 2s

0

#

ds =

" 1

1

#

+

26

6666

64

1

2e

2t

0

37

7777

75 =

26

6666

64 1

1

2e

2t

1

37

7777

75;

¤±,?§3D?^?e)?

’(t) = (t)c(t) =

" et tet

0 et

#2666

6664 1

1

2e

2t

1

37

7777

75 =

26

6666

64 (1 t)e

t 1

2e

t

et

37

7777

75:

N¢?4?[ (wg??) 15ù 06/01/2022 48 / 92

í?

eai(t)(i = 1;2; ;n), f(t)t3?m[a;b]t?Y, xi(t)(i = 1;2; ;n)??

m[a;b]tàg?5???§

x(n) + a1(t)x(n 1) + + an(t)x = 0

?)|,K?àg?5???§

x(n) + a1(t)x(n 1) + + an(t)x = f(t) (1.26)

÷vD?^?

’(t0) = 0;’0(t0) = 0; ;’(n 1)(t0) = 0; t0 2[a;b]

)?L??

’(t) =

nX

k=1

xk(t)

Z t

t0

Wk[x1(s);x2(s); ;xn(s)]

W[x1(s);x2(s); ;xn(s)] f(s)ds; (1.27)

N¢?4?[ (wg??) 15ù 06/01/2022 49 / 92

í?

ù¥, W[x1(s);x2(s); ;xn(s)]′?)|x1(s);x2(s); ;xn(s)Kd?1

a, Wk[x1(s), x2(s); ;xn(s)]′òù¥1k?±(0;0; ;0;1)TO?

1a. @o,?àg?5???§(1.26)??)L??

u(t) = c1x1(t) + c2x2(t) + + cnxn(t) +’(t);

ùpci(i = 1;2; ;n)?(?~ê.

a(1.27)???àg?5???§(1.26)~êC′úa. d?,?àg

?5???§(1.26)?)?

x(t) = c1x1(t) + c2x2(t) + + cnxn(t) +’(t);

ùpci(i = 1;2; ;n)???~ê.

~

??§x00+ x = 0???)|?x1(t) = cost;x2(t) = sint,|éA

?àg?5???§x00+ x = 2tant??).

N¢?4?[ (wg??) 15ù 06/01/2022 50 / 92

):·??±?|^a(1.27)?1|)

W[x1(t);x2(t)] =



cost sint sint cost



= 1;

t0 = 0,Kk

’(t) =

Z t

0

(sintcoss costsins) 2tansds

= 2sint

Z t

0

sinsds 2cost

Z t

0

sinstansds

= 2sint 2costlnjsect + tantj:

|’(t)′ˉK¥?àg?5???§??).q?

?sint′x00+ x = 0??),¤±

2costlnjsect + tantj

?′x00+ x = 2tant??).

N¢?4?[ (wg??) 15ù 06/01/2022 51 / 92

81

1 ?5???§|??n?

?Vg

3??5?n

àg?5???§|

?àg?5???§|

2 ~Xê?5???§|

Y


?)Y
O?

3 A^ˉKT~

N¢?4?[ (wg??) 15ù 06/01/2022 52 / 92

Y
?êexpA

!·?k5??XêY
?~êY
àg?5???§|

x0(t) = Ax(t) (2.1)

?)||),ùpA = (aij)n n?~êY
.

??

A?n n~êY
,Y


1X

k=0

Ak

k! = E + A +

A2

2! + +

Am

m! + = expA

ú??Y
?êexpA,?P?eA,ù¥, E?nü?Y
.

Am?Y
Amg?,·?5?A0 = E; 0! = 1.A?"Y
?,=A = O,

kexpO = E.

N¢?4?[ (wg??) 15ù 06/01/2022 53 / 92

ún

?ê1P

k=0

Ak

k!éu¤kA?′??,?dexpA′??(?Y
.

ún



expAt =

1X

k=0

Aktk

k! (2.2)

3t??k??mt′????.

N¢?4?[ (wg??) 15ù 06/01/2022 54 / 92

5?

eY
A;B??,=AB = BA,K

exp(A + B) = expAexpB:

y2: duAB = BA,Kd?a?n9yé???ê|ê?n?

exp(A + B) =

1X

k=0

(A + B)k

k! =

1X

k=0

0B

BBBB

B@

1X

l=0

AlBk l

l!(k l)!

1C

CCCC

CA

=

1X

l=0

Al

l!

0B

BBBB

B@

1X

k=0

Bk

k!

1C

CCCC

CA = expAexpB:

5?

é??Y
A,Y
?ê_=(expA) 13,?

(expA) 1 = exp( A):

y2:-B = A,B?y.

N¢?4?[ (wg??) 15ù 06/01/2022 55 / 92

5?

eT′??éY
,K

exp(T 1AT) = T 1(expA)T:

y2:

exp(T 1AT) = E +

1X

k=1

(T 1AT)k

k!

= E +

1X

k=1

T 1AkT

k!

= E + T 1

0B

BBBB

B@

1X

k=1

Ak

k!

1C

CCCC

CAT

= T 1(expA)T:

N¢?4?[ (wg??) 15ù 06/01/2022 56 / 92

?n

Y
(t) = expAt

′~Xêàg?5???§|(1.16)?)Y
,? (0) = E.

y2:??

0(t) = (expAt)0

= A + A

2t

1! +

A3t2

2! + +

Aktk 1

(k 1)! +

= AexpAt

= A (t);

¤± (t)′~Xêàg?5???§|(2.1))Y
. q??

(0) = expO = E;

?

Det( (0)) = Det(E) = 1 , 0;

¤± (t)′~Xêàg?5???§|(2.1)?)Y
.

N¢?4?[ (wg??) 15ù 06/01/2022 57 / 92

?n

Y
(t) = expAt

′~Xêàg?5???§|(1.16)?)Y
,? (0) = E.

y2:??

0(t) = (expAt)0

= A + A

2t

1! +

A3t2

2! + +

Aktk 1

(k 1)! +

= AexpAt = A (t);

¤± (t)′~Xêàg?5???§|(2.1))Y
. q??

(0) = expO = E;

?

Det( (0)) = Det(E) = 1 , 0;

¤± (t)′~Xêàg?5???§|(2.1)?)Y
.

N¢?4?[ (wg??) 15ù 06/01/2022 58 / 92

u′,d?n5.5?±~Xêàg?5???§|(2.1)??)?L

??

’(t) = (expAt)c;

c?~ê?t.’(0) = ?,’(t) = (expAt) .

~

A′éY
?,=

A =

26

6666

6666

6666

664

1

2

:::

n

37

7777

7777

7777

775

;

á|?x0(t) = Ax(t)?)Y
.

N¢?4?[ (wg??) 15ù 06/01/2022 59 / 92

): dún?

expAt = E +

26

6666

6666

6666

664

1

2

:::

n

37

7777

7777

7777

775

t

1! +

26

6666

6666

6666

664

21

22

:::

2n

37

7777

7777

7777

775

t2

2! + +

26

6666

6666

6666

664

k1

k2

:::

kn

37

7777

7777

7777

775

tk

k! + =

26

6666

6666

6666

664

e 1t

e 2t

:::

e nt

37

7777

7777

7777

775

:

N¢?4?[ (wg??) 15ù 06/01/2022 60 / 92

~

|?§|x0(t) =

" 1 1

0 1

#

x(t)?)Y
.

): du

A =

" 1 1

0 1

#

=

" 1 0

0 1

#

+

" 0 1

0 0

#

;


ü?Y
′??,K

expAt = exp

" 1 0

0 1

#

t exp

" 0 1

0 0

#

t

=

" et 0

0 et

#



0B

BBBB

@E +

" 0 1

0 0

#

t +

" 0 1

0 0

#2 t2

2! +

1C

CCCC

A:

?)Y
?

expAt = et

" 1 t

0 1

#

:

N¢?4?[ (wg??) 15ù 06/01/2022 61 / 92

?)Y
O?

??

j E Aj= 0; ? Det( E A) = 0: (2.3)

?§(2.3)??~Xêàg?5???§|(2.1)A?§, ??A

?,
?tv??? éAA?t.

du?§(2.3)¤A??1?ó,?ò?)Y
|)??±e

ü??1?1??. (1)A?t?ü?(=Y
AkA

? 1; 2; ; n????ó)?,dt????±e?n.

?n

eY
Akn?p??óA? 1; 2; ; n,@où
A?éAXn

??5?''A?tv1;v2; ;vn,K~Xêàg?5???§

|(2.1)?)Y
?L??

(t) = [e 1tv1;e 2tv2; ;e ntvn]; 1< t < +1:

N¢?4?[ (wg??) 15ù 06/01/2022 62 / 92

y2: dc???·??2, e itvi(i = 1;2; ;n)?~Xêàg?

5???§|(2.1)),?

Det( (0)) = Det([v1;v2; ;vn]) , 0;

d?n?, (t)′~Xêàg?5???§|(2.1)???)Y
.

~

á|?§|

x0(t) = Ax(t);ù¥A =

" 1 2

2 1

#

???)Y
(t),?|)expAt.

N¢?4?[ (wg??) 15ù 06/01/2022 63 / 92

):A?§?

j E Aj=



1 22 1



= ( 1)2 + 4 = 0;

)A? 1 = 1 + 2i; 2 = 1 2i.

 1 = 1 + 2i?,d?§|

( 1E A)v1 = 0

)A?t

v1 = c1

" 1

i

#

; c1???~ê:

 1 = 1 2i?,d?§|

( 2E A)v2 = 0

)A?t

v2 = c2

" i

1

#

; c2???~ê:

N¢?4?[ (wg??) 15ù 06/01/2022 64 / 92

d?n?,Y


(t) =

" e(1+2i)t ie(1 2i)t

ie(1+2i)t e(1 2i)t

#

??§|???)|.

q??

(0) =

" 1 i

i 1

#

;

1(0) = 12

" 1 i

i 1

#

;

¤±

expAt = (t) 1(0) = et

" cos2t sin2t

sin2t cos2t

#

:

5:3?n(5.10)¥, (t)???ò′expAt. d?n(5.7)?,ü??m?

????é~êY
C.

N¢?4?[ (wg??) 15ù 06/01/2022 65 / 92

(2)A? 1; 2; ; k-ê?O?n1;n2; ;nk

?n1 +n2 + +nk = n(ek = n,Káuü??1(1))?,éAuz??nj-

A? j,?5?ê?§|

(A jE)njv = 0 (2.4)

)N¤n??Ap?mU??nj?f?mUj(j = 1;2; ;k),

ù?n??Ap?m?L??U1;U2; ;Uk?ú.@o,éu??

?tu2U,3???t|uj 2Uj(j = 1;2; ;k),|

u = u1 + u2 + + uk:

k = 1?,Y
A?k??A?,?7én??Ap?m?1?);

k = n?, uj = cjvj(j = 1;2; ;n),
vjB′A? j¤éAA?

t, cj?,
~ê.

N¢?4?[ (wg??) 15ù 06/01/2022 66 / 92

????5,·???16k6n?1.??D?^?’(0) = ,K

= v1 + v2 + + vk; (2.5)

ù¥vj 2Uj(j = 1;2; ;k),duf?mUj′d?§|(2.4)),@

ovj??′?§|(2.4)),=k

(A jE)lvj = 0; l>nj; j = 1;2; ;k: (2.6)

u′?

e jtexp( jEt) = e jt

26

6666

6666

6666

664

e jt

e jt

:::

e jt

37

7777

7777

7777

775

= E; (2.7)

(üa(2.6)úa(2.7)

(expAt)vj = (expAt)e jt[exp( jEt)]vj

= e jt[exp(A jE)t]vj

= e jt[E + t(A jE) + t

2

2!(A jE)

2 + + tnj 1

(nj 1)!(A jE)

nj 1]vj:

N¢?4?[ (wg??) 15ù 06/01/2022 67 / 92

da(2.5),éta|ú?

’(t) = (expAt) = (expAt)

kX

j=1

vj =

kX

j=1

(expAt)vj

=

kX

j=1

e jt[E + t(A jE) + t

2

2!(A jE)

2 + + tnj 1

(nj 1)!(A jE)

nj 1]vj:

?d,~Xêàg?5???§|(2.1)÷v’(0) = )?

’(t) =

kX

j=1

e jt

0B

BBBB

BB@

nj 1X

i=0

ti

i!(A jE)

i

1C

CCCC

CCAvj: (2.8)

AO/,A?k??A??,?7
)D??t ,Ké???tu?

k

(A E)nu = 0;

=(A E)n?"Y
. u′

expAt = e texp(A E)t = e t

n 1X

i=0

(A E)i t

i

i!: (2.9)

N¢?4?[ (wg??) 15ù 06/01/2022 68 / 92

¢St,·???±lúa(2.8)¥?|?expAt,??

expAt = (expAt)E = [(expAt)e1;(expAt)e2; ;(expAt)en];

ù¥

e1 =

26

6666

6666

6666

6666

6666

4

1

0

:::

0

0

37

7777

7777

7777

7777

7777

5

;e2 =

26

6666

6666

6666

6666

6666

4

0

1

:::

0

0

37

7777

7777

7777

7777

7777

5

; ;en =

26

6666

6666

6666

6666

6666

4

0

0

:::

0

1

37

7777

7777

7777

7777

7777

5

′ü??t. d’(t) = (expAt) ?,O??)Y
expAt¢St?I?ò

D??t ?O?

= e1; = e2; ; = en;

|n?)??,B?E?Y
expAt.

N¢?4?[ (wg??) 15ù 06/01/2022 69 / 92

~

á|?§|

x0(t) = Ax(t); ù¥A =

" 2 1

1 2

#

???)Y
(t),?|)expAt.

):A?§?

j E Aj=



2 1 1 2



= ( 1)( 3) = 0;

)A? 1 = 1; 2 = 3.

 1 = 1?,d?§|

( 1E A)v1 = 0

?A?t

v1 = c1

" 1

1

#

; c1???"??~ê:

N¢?4?[ (wg??) 15ù 06/01/2022 70 / 92

 2 = 3?,d?§|

( 2E A)v2 = 0

?A?t

v2 = c2

" 1

1

#

; c2???~ê:

d?n?,?§???)|?

(t) =

" et e3t

et e3t

#

:

q??

(0) =

" 1 1

1 1

#

;

1(0) = 12

" 1 1

1 1

#

;

¤±

expAt = (t) 1(0) = 12

" et + e3t e3t et

e3t et et + e3t

#

:

N¢?4?[ (wg??) 15ù 06/01/2022 71 / 92

~

|)D?ˉKx0(t) = Ax(t);’(0) = ,ù¥A =

" 2 1

1 4

#

,?|expAt.

): dA?§

j E Aj=



2 11 4



= 2 6 + 9 = 0

) = 3?A-A?,A?t

v = c1

" 1

1

#

; c1???~ê?c1 , 0:

??Y
A?k??A?,=?k??f?mU1,P =

"

1

2

#

;Kk

’(t) = e3t[E + t(A 3E)]

= e3t

"

1 + t( 1 + 2)

2 + t( 1 + 2)

#

:

N¢?4?[ (wg??) 15ù 06/01/2022 72 / 92

dúa(2.8)?

expAt = e3t[E + t(A 3E)]

= e3t

" 1 0

0 1

#

+ t

" 1 1

1 1

#!

= e3t

" 1 t t

t 1 + t

#

:

~

e

A =

26

6666

6666

6666

6666

664

3 1

3 1

3

3

3

37

7777

7777

7777

7777

775

;

á|?expAt.

N¢?4?[ (wg??) 15ù 06/01/2022 73 / 92

): dA?§j E Aj= 0?) = 3?Y
Aê-A?,?

(A + 3E)3 = 0:

?d,dúa(2.8)?

expAt = e 3t



E + t(A + 3E) + t

2

2!(A + 3E)

2

!

= e 3t

26

6666

6666

6666

6666

6666

664

1 t t

2

2! 0 00 1 t 0 0

0 0 1 0 0

0 0 0 1 0

0 0 0 0 1

37

7777

7777

7777

7777

7777

775

:

N¢?4?[ (wg??) 15ù 06/01/2022 74 / 92

~

á|?§|

x0(t) = Ax(t); ù¥A =

26

6666

6664

0 1 1

1 1 1

0 1 1

37

7777

7775

÷vD?^?’(0) = )’(t),9?)Y
expAt.

): dA?§

j E Aj=







1 1

1 + 1 1

0 1 + 1





= ( + 1)2 = 0

)ü? 1 = 0ú-? 2 = 1.

 1 = 0?,A?t?

u =

26

6666

6664

2

1

1

37

7777

7775; ???"??~ê:

N¢?4?[ (wg??) 15ù 06/01/2022 75 / 92

 2 = 1?,A?t?

v =

26

6666

6664







37

7777

7775; ; ???"??~ê:

?d,f?mU1d?tuü¤,f?mU2d?tvü¤.éD??t ?1


),-z1 2U1;z2 2U2; = [ 1; 2; 3]T,@ok

z1 + z2 =

26

6666

6664

2

1

1

37

7777

7775 +

26

6666

6664







37

7777

7775 =

26

6666

6664

2 +

+

+

37

7777

7775 =

26

6666

6664

1

2

3

37

7777

7775:

)

= 1 3; = 2 3 1; = 2 1 + 3:

u′k

z1 =

26

6666

6664

2( 1 3)

1 3

1 3

37

7777

7775; z2 =

26

6666

6664

2 3 1

2 1 + 3

2 3 1

37

7777

7775:

N¢?4?[ (wg??) 15ù 06/01/2022 76 / 92

dúa(2.8)?,÷vD?^?’(0) = )?

’(t) = e 1tEz1 + e 2t(E + t(A + E))z2

= z1 + e t(E + t(A + E))z2

=

26

6666

6664

2( 1 3)

1 3

1 3

37

7777

7775 + e t

26

6666

6664

2 3 1 + t( 1 + 2 + 3)

2 1 + 3

2 3 1 + t( 2 1 + 3)

37

7777

7775:

?O = [1;0;0]T;[0;1;0]T;[0;0;1]T,?3??5?'')

’1(t) =

26

6666

6664

2 e t(1 + t)

1 e t

1 e t(1 + t)

37

7777

7775;’2(t) =

26

6666

6664

te t

e t

te t

37

7777

7775;’3(t) =

26

6666

6664

2 + (2 + t)e t

1 + e t

1 + (2 + t)e t

37

7777

7775;

?d

expAt =

26

6666

6664

2 (1 + t)e t te t 2 + (2 + t)e t

1 e t e t 1 + e t

1 (1 + t)e t te t 1 + (2 + t)e t

37

7777

7775:

N¢?4?[ (wg??) 15ù 06/01/2022 77 / 92

~

|?§| 8

>>><

>>>:

x01 = 2x1 + 2x2 2x3;

x02 = 2x1 + 5x2 4x3;

x03 = 2x1 4x2 + 5x3;

÷vD?^?’(0) = )’(t),?|expAt.

): XêY


A =

26

6666

6664

2 2 2

2 5 4

2 4 5

37

7777

7775;

dA?§)A? 1 = 10?ü?, 2 = 1?-?.

 1 = 10?,éAA?t

u = c1

26

6666

6664

1

2

2

37

7777

7775; c1???~ê:

N¢?4?[ (wg??) 15ù 06/01/2022 78 / 92

 2 = 1?,éAA?t

v =

26

6666

6664

2c2 + 2c3

c2

c3

37

7777

7775; c2;c3???~ê:

?d,f?mU1′d?tu¤ü¤,f?mU2′d?tv¤ü¤.

-z1 2U1;z2 2U2; = [ 1; 2; 3]T,ó~(5.12)?)

z1 = 19

26

6666

6664

1 + 2 2 2 3

2( 1 + 2 2 2 3)

2( 1 + 2 2 2 3)

37

7777

7775; z2 = 19

26

6666

6664

8 1 2 2 + 2 3

2 1 + 5 2 + 4 3

2 1 + 4 2 + 5 3

37

7777

7775:

dd?÷vD?^?’(0) = )?

’(t) = e10tEz1 + et(E + t(A E))z2

= 19e10t

26

6666

6664

1 + 2 2 2 3

2( 1 + 2 2 2 3)

2( 1 + 2 2 2 3)

37

7777

7775 + 19et

26

6666

6664

8 1 2 2 + 2 3

2 1 + 5 2 + 4 3

2 1 + 4 2 + 5 3

37

7777

7775:

N¢?4?[ (wg??) 15ù 06/01/2022 79 / 92

?O = [1;0;0]T;[0;1;0]T;[0;0;1]T,?\ta3??5?'')

’1(t) = 19

26

6666

6664

e10t + 8et

2e10t 2et

2e10t + 2et

37

7777

7775;’2(t) = 19

26

6666

6664

2e10t 2et

4e10t + 5et

4e10t + 4et

37

7777

7775;’3(t) = 19

26

6666

6664

2e10t + 2et

4e10t + 4et

4e10t + 5et

37

7777

7775:

u′

expAt = 19

26

6666

6664

e10t + 8et 2e10t 2et 2e10t + 2et

2e10t 2et 4e10t + 5et 4e10t + 4et

2e10t + 2et 4e10t + 4et 4e10t + 5et

37

7777

7775:

5:éu?)Y
){,?k, ü?~??{.??′òùz?e

(Jordan)IO/., ??′|^M??-p4(Hamilton-Cayley)?n.

N¢?4?[ (wg??) 15ù 06/01/2022 80 / 92

éu?àg?5???§|

x0 = Ax + f(t) (2.10)

d5.1!¥a(1.25)?±??)’(t)O?úa.?? (t) = expAt,¤±

1(s) = exp( As);

1(t0) = exp( At0):

’(t0) = ?,òt?üa?\a(1.25),?

’(t) = exp[A(t t0)] +

Z t

t0

exp[A(t s)]f(s)ds: (2.11)

a(2.11)??
|)~Xê?àg?5???§|?{.

N¢?4?[ (wg??) 15ù 06/01/2022 81 / 92

~

|?§|

x0 = Ax + f(t); A =

" 1 2

2 1

#

; f(t) =

" et

0

#

;

÷vD?^?

’(0) =

" 0

1

#

)’(t).

): d~5.8?

expAt = et

" cos2t sin2t

sin2t cos2t

#

;

N¢?4?[ (wg??) 15ù 06/01/2022 82 / 92

): d~5.8?

expAt = et

" cos2t sin2t

sin2t cos2t

#

;

?\a(2.11)

’(t) = et

" cos2t sin2t

sin2t cos2t

#" 0

1

#

+

Z t

0

et s

" cos2(t s) sin2(t s)

sin2(t s) cos2(t s)

#" es

0

#

ds

= et

" sin2t

cos2t

#

+ et

Z t

0

" cos2(t s)

sin2(t s)

#

ds

= et

" sin2t

cos2t

#

12et

" sin2t

1 cos2t

#

=

26

6666

6666

664

3

2e

t sin2t

1

2e

t(3cos2t 1)

37

7777

7777

775:

N¢?4?[ (wg??) 15ù 06/01/2022 83 / 92

?,·?0 X?|^.ê.dC?{|?)Y
.

???t?ê.ê.dC??

£[f(t)] =

Z +1

0

e stf(t)dt; (2.12)

ù¥, f(t)′n??t?ê,§z???t?3.ê.dC?.A^.

ê.dC??±ò|)?5???§|ˉKz?|)?5?ê?§|

ˉK.

~

|^.ê.dC?(2.12)|)~14.

): ò?§|??t/a

( x0

1 = x1 + 2x2 + e

t;

x02 = 2x1 + x2: (2.13)

D?^??x1(0) = 0;x2(0) = 1.

N¢?4?[ (wg??) 15ù 06/01/2022 84 / 92

-

X1(s) = £[x1(t)]; X2(s) = £[x2(t)];

é?§|(2.13)?1.ê.dC?8

>>><

>>>: (s 1)X1(s) 2X2(s) =

1

s 1;2X

1(s) + (s 1)X2(s) = 1:

u′)

8>>

>>>>

>>><

>>>>

>>>>

>:

X1(s) = 3(s 1)2 + 22 = 32 2(s 1)2 + 22;

X2(s) =

s 1 2s 1

(s 1)2 + 22 =

3

2(s 1)

(s 1)2 + 22

1

2

s 1:

dL4-1 (.ê.dC?L)B?

x1(t) = 32et sin2t; x2(t) = 32et cos2t 12et:

ù?~14(J??.

N¢?4?[ (wg??) 15ù 06/01/2022 85 / 92

~

|^.ê.dC?{|?§|

( x0

1 = x1 + 2x2;x0

2 = x1 + x2;

÷vD?^?’1(0) = 0;’2(0) = 1)’1(t);’2(t),?|?§?)Y
.

):-

X1(s) = £[’1(t)]; X2(s) = £[’2(t)]:

b

x1 = ’1(t); x2 = ’2(t)

÷v?§|,é?§|?1.ê.dC??

( (s 1)X

1(s) 2X2(s) = ’1(0) = 0;

X1(s) + (s 1)X2(s) = ’2(0) = 1;

N¢?4?[ (wg??) 15ù 06/01/2022 86 / 92

= 8

>>>>

>><

>>>>

>>:

X1(s) = 2(s 1)2 + 2;

X2(s) = s 1(s 1)2 + 2:

dL4-1 (.ê.dC?L)?

( ’

1(t) =

p2et sinp2t;

’2(t) = et cosp2t:

?
E?)Y
,·?I?2|?÷vD?^?

1(0) = 1; 2(0) = 0

)( 1(t); 2(t)). aqt?C?L§?

( (s 1)X

1(s) 2X2(s) = 1(0) = 1;

X1(s) + (s 1)X2(s) = 2(0) = 0;

N¢?4?[ (wg??) 15ù 06/01/2022 87 / 92

) 8

>>>>

>><

>>>>

>>:

X1(s) = s 1(s 1)2 + 2;

X2(s) = 1(s 1)2 + 2:

L4-1 8

>>><

>>>:

1(t) = et cosp2t;

2(t) = 1p2et sinp2t:

?d,?§|?)Y
?

(t) =

" ’

1(t) 1(t)

’2(t) 2(t)

#

=

26

6666

6664

p2et sinp2t et cosp2t

et cosp2t 1p2et sinp2t

37

7777

7775:

N¢?4?[ (wg??) 15ù 06/01/2022 88 / 92

81

1 ?5???§|??n?

?Vg

3??5?n

àg?5???§|

?àg?5???§|

2 ~Xê?5???§|

Y


?)Y
O?

3 A^ˉKT~

N¢?4?[ (wg??) 15ù 06/01/2022 89 / 92

(0k?u?) 0k?′#??;?§?¥

?§l
?U??NS¤k0§é?úk?¥1kL?0. u?

0k?~^?{′?:0Ftu?(GTT)§B?\?Jt?:

0,,3?ó?mu??:0?Y(G)ú-?à?Y(H)§à§?Cz

?1???. 20-V60c?,{IAckermanJ?
{′u?.. b

8>>

>>><

>>>>

>:

dG

dt = F1(G;H) + J(t);

dH

dt = F2(G;H);

ù¥, J(t)?ú?é0?YO\ ü??.m???2?G

( F

1(G0;H0) = 0;

F2(G0;H0) = 0:

?C?

g = G G0;h = H H0

N¢?4?[ (wg??) 15ù 06/01/2022 90 / 92

?ù? ?§

8>>

>>><

>>>>

>:

dg

dt = F1(G0 + g;H0 + h) + J(t);

dh

dt = F2(G0 + g;H0 + h):

òmà?êDm{z?? ?"1;"2,?P

m1 = @F1(G0;H0)@G ; m2 = @F1(G0;H0)@H ;

m4 = @F2(G0;H0)@G ; m3 = @F2(G0;H0)@H ;

K?§|?±z?

8>>

>>><

>>>>

>:

dg

dt = m1g m2h + J(t);

dh

dt = m3h + m4g;

(3.1)

ù¥, mit?~ê.ùB′0k?u?..

N¢?4?[ (wg??) 15ù 06/01/2022 91 / 92

(?ì?.) d>′ú?C?|C¤[^N?ì.′?

?~???§|.???C>
>?E(t)°?X???U?ì,l
|

(ì?u)?.U?ì?t′[^|Sgd$?.Cz

>6?L??,?3[^N^?ú>6)^??p?^e

?1$?.PU?ì=zXê?T, f?U?ì?(ì?p?^?,

R?U?ì>{, L?U?ìaAXê.?t?m(ì?′??

?k{Z?Xú?.{ZXê?C,?5Xê?k,u′k''

Xa

e = Tdxdt; f = Ti:

ù¥, e??üà>?ü, x???£, x0???Y.dú?1

??9£′>???,????§|

8>>

>>>>

<>

>>>>

>:

md

2x

dt2 + c

dx

dt + kx = Ti;

Tdxdt + Ldidt + Ri = E(t):

(3.2)

N¢?4?[ (wg??) 15ù 06/01/2022 92 / 92

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