faseportrait-ziyadatur (12610007)

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Nama: Ziyadatur R.F. NIM: 12610007 Misalkan matriks A = [ a b p q ] = [ 7 1 6 2 ] dx dt =ax +by dx dt =7 x+ y dy dt =px +qy dy dt =6 x+ 2 y Mencari nilai Eigen [ x' y' ] = [ 7 1 6 2 ][ x y ] det ( A λI) =0 det ( [ 7 1 6 2 ] λ [ 1 0 0 1 ] ) =0 det ( [ 7 1 6 2 ] [ λ 0 0 λ ] ) =0 det ( [ 7λ 1 6 2λ ] ) =0 ( 7λ )( 2λ ) 6=0 14 2 λ7 λ +λ 2 =0 λ 2 9 λ +8=0

Transcript of faseportrait-ziyadatur (12610007)

Page 1: faseportrait-ziyadatur (12610007)

Nama: Ziyadatur R.F.

NIM: 12610007

Misalkan matriks

A=[ a bp q]=[7 1

6 2] dxdt

=ax+by

dxdt

=7 x+ y

dydt

=px+qy

dydt

=6 x+2 y

Mencari nilai Eigen

[ x 'y ' ]=[7 16 2][ xy ]

det (A−λI )=0

det ([7 16 2]−λ [1 0

0 1 ])=0

det ([7 16 2]−[λ 0

0 λ ])=0

det ([7−λ 16 2−λ])=0

(7−λ ) (2− λ )−6=0

14−2 λ−7 λ+λ2=0

λ2−9 λ+8=0

( λ−1 )(λ−8)

λ1=1 dan λ2=8

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Untuk λ1=1

Au=λu

[7 16 2][u1

u2]=1 [u1

u2]

7u1+u2=u1

6u1+2u2=u2

6u1=−u2

6u1=−u2

u1

u2

= 1−6

Maka [u1

u2]=[ 1

−6]

Untuk λ2=8

Av=λ v

[7 16 2][v1

v2]=1[v1

v2]

7 v1+v2=8v1

6 v1+2 v2=8v2

−v1=−v2

6 v1=6v2

v1

v2

=66

Maka [v1

v2]=[11]

Misalkan

x (0 )=7 dan y (0 )=7

( x 'y ')=C1(u1

u2)eλt−C2(v1

v2)e λt

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( x 'y ')=C1( 1−6)e t−C2(11)e8 t

Maka

(77)=C1( 1−6)e(0 )−C2(1

1)e(0)

7=C1−C2

7=−6C1−C2

Maka didapatkan C1=−14

5 dan C2=

−495

Sehingga didapatkan solusi umumnya adalah

( xy )=−145 ( 1

−6)e t+ 495 (11)e8 t

Program matlab

restart;

with(DEtools);

phaseportrait([diff(X(t), t) = 7*X(t)-Y(t), diff(Y(t), t) = 6*X(t)+2*Y(t)], [X(t), Y(t)], t = 0 .. 10, {[X(0) = 7, Y(0) = 7]});

phaseportrait([diff(X(t), t) = 7*X(t)-Y(t), diff(Y(t), t) = 6*X(t)+2*Y(t)], [X(t), Y(t)], t = 0 .. 10, {[X(0) = -7, Y(0) = -7]});

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phaseportrait([diff(X(t), t) = 7*X(t)-Y(t), diff(Y(t), t) = 6*X(t)+2*Y(t)], [X(t), Y(t)], t = 0 .. 10, {[X(0) = -7, Y(0) = 7]});

phaseportrait([diff(X(t), t) = 7*X(t)-Y(t), diff(Y(t), t) = 6*X(t)+2*Y(t)], [X(t), Y(t)], t = 0 .. 10, {[X(0) = 7, Y(0) = -7]});