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Task compilation of differential equation II lecture
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BilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationBilingualMathematicsEducationhjklzxcvbnmqwertyuiopasdfghjklzxcvbnmqwertyuiopasdfghjklzxcvbnmqw
DIFFERENTIAL EQUATION II
TASK COMPILATION
3/27/2014
MARIA PRISCILLYA PASARIBUIDN. 4103312018
TASK I (February, 13th 2014)
Determine the solution of::
1.d2 yd t2
−2dydt
−5 y=0, y(0)=0; y’(0)=1
2.d2 yd t2
−3dydt
=0, y(0)=0; y’(0)=1
3.d2 yd t2
−4dydt
−4 y=0, y(0)=0; y’(0)=1
Solution:
1.d2 yd t2
−2dydt
−5 y=0, y(0)=0; y’(0)=1
Characteristic Equation: λ2−2 λ−5=0
λ1,2=−b±√b2−4 ac
2a=
−(−2 )±√ (−2 )2−4 (1 ) (−5 )2 (1 )
¿ 2±√4+202
=2±√242
=2±2√62
=1±√6
λ1and λ2 are real and distinct, then y=c1 em1x+c2 e
m2 x
y (0 )=0
0=c1+c2
c1=−c2 .................... (1)
y ' (0 )=1
y ' (x )= (1+√6 )c1e(1+√6 )x+(1−√6 )c1 e
(1−√6) x
1=(1+√6 ) c1+(1−√6 )c2
1=(1+√6 ) c1+(1−√6 )(−c¿¿1)¿
1=c1 (1+√6−1+√6 )
1=2√6c1
c1=1
12√6
c1=−c2 .................... (1)
c2=−112
√6
Maka, y=1
12√6e (1+√6 ) x− 1
12√6e (1−√6) x
2.d2 yd t2
−3dydt
=0, y(0)=0; y’(0)=1
Characteristic Equation:λ2−3 λ=0
λ (λ−3)=0
λ1=0∨ λ2=3
λ1and λ2 are real and distinct, then y=c1 em1x+c2 e
m2 x
y=c1 e0x+c2 e
3 x
y (0 )=0
0=c1+c2
c1=−c2 .................... (1)
y ' (0 )=1
y ' (x )=3c23 x
1=3c2
c2=13
c1=−13
Then, y=−13em1 x+ 1
3em2 x
3.d2 yd t2
−4dydt
−4 y=0, y(0)=0; y’(0)=1
Characteristic Equation:λ2−4 λ−4=0
λ1,2=−b±√b2−4 ac
2a=
−(−4 )±√ (−4 )2−4 (1 ) (−4 )2 (1 )
¿ 4±√16+162
=4 ±4√22
=2±2√2
λ1and λ2 are real and distinct, then y=c1 em1x+c2 e
m2 x
y=c1 e(2+2√2) x+c2 e
(2−2√2 )x
y (0 )=0
0=c1+c2
c1=−c2 .................... (1)
y ' (0 )=1
y ' (x )= (2+2√2 )c1 e( 2+2√2)x+(2−2√2)c2e
(2−2√2)x
1=( 2+2√2 ) c1+(2−2√2)c2
1=( 2+2√2 ) c1+(2−2√2)(−c1)
1=c1(2+2√2−2+2√2)
1=c1(4√2)
c1=18
√2
c1=−c2 .................... (1)
c2=−18
√2
Maka, y=18
√2e(2+2√2) x−18√2e(2−2√2) x
TASK II (February, 20th 2014)
Solve these equation:
1.d4 yd x4 +10
d2 yd x2 +9 y=0
2.d4 yd x4 + d
3 yd x3 + d
2 yd x2 +2 y=0
3. y ' ' '+4 y '=0
4. y ( 4)+4 y ' '− y '+6 y=0
5.d6 yd x6 −4
d5 yd x5 +16
d4 yd x4 −12
d3 yd x3 +41
d2 yd x2 −8
dydx
+26 y=0
Solution:
1.d4 yd x4 +10
d2 yd x2 +9 y=0
Characteristic equation: λ4+10 λ2+9=0
(λ2+9 ) (λ2+1 )=0
( λ+3i ) ( λ−3 i) ( λ+i ) ( λ−i )=0
λ1=−3 i⋁ λ2=−3 i⋁ λ3=−i⋁ λ3=i
So, the solution is y=C1 cos3 x+C2 sin3 x+C3cos x+C4 sin x
2.d4 yd x4 + d
3 yd x3 + d
2 yd x2 +2 y=0
Characteristic equation: λ4+λ3+ λ2+2=0
(λ2−λ+1 ) ( λ2+2 λ+2 )=0
(λ2−λ+1 )=0
λ1,2=−b±√b2−4 ac
2a
λ1,2=−(−1)±√(−1)2−4(1)(1)
2(1)
λ1,2=1±√1−4
2
λ1,2=1±√3i
2
λ1=12+ 1
2√3i and λ2=
12−1
2√3 i
(λ2+2λ+2 )=0
λ3,4=−b±√b2−4ac
2a
λ3,4=−(2)±√(2)2−4 (1)(2)
2(1)
λ3,4=−2±√4−8
2
λ3,4=−2±2 i
2
λ3=−1+i and λ4=−1−i
So, the solution is y=e12x(C1 cos
12
√3 x+C2sin12√3x )+e−x (C3 cos x+C4 sin x )
3. y ' ' '+4 y '=0
Characteristic equation: λ3+4 λ=0
λ ( λ2+4 )=0
λ ( λ+2i ) ( λ−2i )=0
λ1=0⋁ λ2=−2 i⋁ λ3=2 i
So, the solution is y=C1+C2cos2 x+C3 sin 2x
4. y ( 4)+4 y ' '− y '+6 y=0
Characteristics equation is λ4+4 λ2− λ+6=0
(λ2−λ+2 ) ( λ2+λ+3 )=0
(λ2−λ+2 )=0
λ1,2=−b±√b2−4 ac
2a
λ1,2=−(−1)±√(−1)2−4(1)(2)
2(1)
λ1,2=1±√1−8
2
λ1,2=1±√7 i
2
λ1=12+ 1
2√7 i and λ2=
12−1
2√7 i
(λ2+ λ+3 )=0
λ3,4=−b±√b2−4ac
2a
λ3,4=−(1 )±√ (1 )2−4 (1 ) (3 )
2 (1 )
λ3,4=−1±√1−12
2
λ3,4=−1±√11i
2
λ3=−1
2+ 1
2√11 i and λ4=
−12
−12√11 i
So, the equation is:
y=e12x(C1 cos
12
√7 x+C2sin12√7 x)+e
−12x(C3 cos
12
√11 x+C4 sin12
√11 x )
5.d6 yd x6 −4
d5 yd x5 +16
d4 yd x4 −12
d3 yd x3 +41
d2 yd x2 −8
dydx
+26 y=0
Characteristic equation is λ6−4 λ5+16 λ4−12 λ3+41 λ2−8 λ+26=0
(λ4+3 λ2+2 ) ( λ2−4 λ+13 )=0
(λ2+1 ) ( λ2+2 ) (λ2−4 λ+13 )=0
(λ2+1 )=0
λ1,2=−b±√b2−4 ac
2a
λ1,2=0±√0−4 (1)(1)
2 (1)
λ1,2=±√−4
2
λ1,2=±2 i
2
λ1=i and λ2=−i
(λ2+2 )=0
λ3,4=−b±√b2−4ac
2a
λ3,4=0±√0−4 (1 ) (2 )
2 (1 )
λ3,4=±√−8
2
λ3,4=±2√2 i
2
λ3=√2i and λ4=−√2 i
(λ2−4 λ+13 )=0
λ5,6=−b±√b2−4ac
2a
λ5,6=−(−4)±√(−4)2−4 (1 ) (13 )
2 (1 )
λ5,6=4±√16−52
2
λ5,6=4±6 i
2
λ5=2+3 i and λ6=2−3 i
So, the solution is
y=C1 cos x+C1 sin x+e2 x (C3cos 3x+C4 sin 3 x )+C5 cos√2x+C5sin √2 x
TASK III (March 7th, 2014)
1.d3qd t 3
−5d2qd t2
+25dqdt
−125q=−60 e7 t
y(0)=0, y’(0)=1, y”(0)=2
2. y(IV )−6 y ' ' '+16 y ' '+54 y '−225 y=100e−2x
y (0 )= y ' (0 )= y ' ' (0 )= y ' ' ' (0 )=1
Solution:
1.d3qd t 3
−5d2qd t2
+25dqdt
−125q=−60 e7 t
y(0)=0, y’(0)=1, y”(0)=2
Quadratic equation: λ3−5 λ2+25 λ−125=−60e7 t
Y= yl + yr
λ3−5 λ2+25 λ−125=0
(λ−5¿(λ+5 i)(λ−5 i)=0
y l=c1 e5 t+c2 cos5 t+c3 sin 5 t
yr=A0 e7 t
yr'=7 A0 e
7t
yr' '=49 A0 e
7 t
yr' ' '=343 A0e
7 t
y ' ' '−5 y ' '+25 y−125 y=−60e7 t
343 A0 e7 t−245 A0e
7 t+175 A0e7 t−125 A0 e
7 t=−60e7 t
148 A0 e7 t=−60 e7 t
A0=−60148
=−1537
yr=−1537
e7 t
Then, we got the equation is equal to
Y= yl + yr
y (t )=c1 e5 t+c2 cos5 t+c3sin 5 t−15
37e7 t
Now, we are going to find the value of c1, c2, and c3.
y(0)=0
0=c1+c2−1537
c1+c2=1537
........................................ (1)
y’(0)=1
y ' (t)=5 c1 e5t−5c2 sin5 t+5c3cos 5t−105
37e7 t
1=5c1+5c3−10537
c1+c3=142185
.................................... (2)
y”(0)=2
y ' '( t)=25c1 e5 t−25c2cos 5t−25 c3 sin 5 t−735
37e7 t
2=25c1−25c2−73537
25c1−25c2=80937
c1−c2=809925
....................................... (3)
Elimination of c2 from (1) and (3)
c1−c2=809925
....................................... (3)
c1+c2=1537
........................................ (1)
2c1=809+375
925
c1=592925
From (3), we can get the value of c2 by substituting the value of c1.
c1−c2=809925
....................................... (3)
592925
−c2=809925
c2=−217925
From (2), we can get the value of c3 by substituting the value of c1.
c1+c3=142185
.................................... (2)
592925
+c3=142185
c3=118925
After getting the value of c1, c2, and c3, then the equation is:
y (t )=592925
e5 t−217925
cos5 t+ 118925
sin 5 t−1537e7t
2. y ( IV )−6 y ' ' '+16 y ' '+54 y '−225 y=100e−2x
y (0 )= y ' (0 )= y ' ' (0 )= y ' ' ' (0 )=1
Quadratic equation: λ4−6 λ3+16 λ2+54 λ−225=100e−2x
+
y= y l+ yr
λ4−6 λ3+16 λ2+54 λ−225=0
By using Horner method and ABC formula, so that the roots are gotten:
λ1=3 λ3=3+4 i
λ2=−3 λ4=3−4 i
y l=c1 e3 t+c2 e
−3 t+e3t (c3 cos4 t+c4 sin 4 t)
yr=A0 e−2x
yr'=−2 A0 e
−2t
yr' '=4 A0 e
−2 t
yr' ' '=−8 A0 e
−2t
yr(IV )=16 A0 e
−2 t
y ( IV )−6 y ' ' '+16 y ' '+54 y '−225 y=100e−2 t
16 A0 e−2 t+48 A0 e
−2t+64 A0 e−2 t−108 A0 e
−2 t−225 A0 e−2 t=100e−2 t
−205 A0 e−2 t=100e−2 t
A0=−100205
=−2041
So, the value of yr is
yr=−20
41e−2 t
y=c1 e3 t+c2 e
−3t+e3 t(c3 cos4 t+c4sin 4 t)−2041e−2 t
Now, we are going to find the value of c1, c2, and c3.
y(0) = 1
1=c1+c2+c3−2041
c1+c2+c3=6141
....................................... (1)
y’(0)=1
y '=3c1 e3 t−3c2e
−3 t+3e3 t (c3 cos 4 t+c4 sin 4 t )+e3 t (−4 c3sin 4 t+4c4 cos 4 t )+ 4041e−2 t
1=3c1−3 c2+3c3+4 c4+4041
3c1−3c2+3c3+4c4=141
........................ (2)
y’’(0)=1
y ' '=9c1 e3 t+9c2 e
−3 t+9e3 t (c3 cos4 t+c 4sin 4 t )+3e3 t (−4c3 sin 4 t+4 c4 cos 4 t )+3e3 t (−4c3 sin 4 t+4 c4 cos4 t )−16e3 t (c3cos 4 t+c4 sin 4 t )+ 8041e−2t
1=9c1+9c2+9c3+12c4+12c4−16 c3−8041
1=9(c1+c2+c3)+24 c4−16c3−8041
12141
=9( 6141
)+24 c4−16 c3
−42841
=24 c4−16 c3
2c3−3c4=10782
.......................................... (3)
y’’’(0)=1
y ' ' '=27 c1 e3 t−27 c2 e
−3 t+75e3 t (c3 cos4 t+c4 sin 4 t )−100e3t (−c3sin 4 t+c4 cos4 t )+ 16041e−2t
1=27 c1−27c2+75 c3−100c4+16041
27c1−27 c2+75c3−100c4=−119
41 ........ (4)
To get the value of c1, c2, c3, and c4, we can use elimination and substituion method from the
above equations.
From (4) and (2), we can get the new equation:
27c1−27 c2+75c3−100c4=−119
41 ........ (4)
27c1−27 c2+27c3+36c4=9
41 ................ (2)
43 c3−136c4=−128
41
6c3−176 c4=−1641
..................................... (5)
From (5) and (3), we can get the value of c4.
6c3−176 c4=−1641
..................................... (5)
6c3−9c4=32182
... ....................................... (3)
−8c4=−32−321
82
c4=−353656
From (3), we can get the value of c3.
2c3−3(−353656
)=10782
.......................................... (3)
2c3=1915656
c3=19151315
+
+
From (1), we get:
c1+c2+19151315
=6141
....................................... (1)
c1+c2=37
1312 ................................................ (6)
From (2), we get:
3c1−3c2+3( 19151315
)+4 (−353656
)= 141
........................ (2)
3c1−3c2=32−5745−2824
1312
3c1−3c2=−85371312
c1−c2=−85373936
................................................ (7)
From (6) and (7), we can get the value of c1 and c2 by elimination method.
c1+c2=37
1312 ................................................ (6)
c1−c2=−85373936
............................................. (7)
2c1=−8537+111
3936
2c1=−84263936
c1=−42133936
From (7), we can get the value of c2.
−42133936
−c2=−85373936
............................................. (7)
c2=8537−4213
3936
+
c2=1081656
After getting the value of c1, c2, c3, and c4, we get the characteristic value.
y=−42133936
e3 t+ 1081656
e−3 t+e3 t( 19151315
cos4 t−353656
sin 4 t )−2041e−2 t
TASK IV (March 13th, 2014)
1.d2qd t 2
+1000dqdt
+25000q=24
q ( 0 )=q ' (0 )=0
2.d2 yd t2
−4dydt
+ y=2t 3+3 t2−1
y (0 )= y ' (0 )=1
Solution:
1. q ' '+1000q '+25000q=24
Quadratic equation:
t 2+1000 t+25000=0
t 1,2=−b±√b2−4 ac
2a
t 1,2=−1000±√(1000)2−4 (1 ) (25000 )
2 (1 )
t 1,2=−1000±√900000
2
t 1,2=−1000±300√10
2
t 1,2=−500±150√10
t 1=−500+150√10 and t 2=−500−150√10
q l=c1 e(−500+150 √10 )t+c2e
(−500−150 √10 )t
qr=A0
q ' r=0
q ' ' r=0
q ' '+1000q '+25000q=24
0+1000 (0)+25000(A0)=24
A0=3
3125, then
qr=3
3125
q=q l+qr
q (t)=c1 e(−500+150 √10) t+c2 e
(−500−150√10) t+ 33125
q ( 0 )=0
0=c1+c2+3
3125
c1+c2=−3
3125 ...................................(1)
q ' (t)= (−500+150√10 ) c1 e(−500+150 √10) t+(−500−150√10 )c2 e
(−500−150√10) t
q ' (0 )=0
0=(−500+150√10 )c1+(−500−150√10 )c2 ........................... (2)
By using elimination method, we can find the value of c1 from (1) and (2).
(−500−150√10 )c1+(−500−150√10 )c2=−3
3125(−500−150√10 )
(−500+150√10 )c1+ (−500−150 √10 )c2=0
−300√10c1=−3
3125(−500−150√10 )
c1=−5√10−15
3125
By using (1), we can find the value of c2.
c1+c2=−3
3125
−5√10−153125
+c2=−3
3125
c2=5√10+12
3125
After finding the value of c1 and c2, we get the equation.
q (t)=(−5√10−153125 )e (−500+150 √10) t+( 5√10+12
3125 )e (−500−150√10) t+ 33125
2. y ' '−4 y '+ y=2t 3+3 t2−1
Quadratic equation:
t 2−4 t+1=0
t 1,2=−b±√b2−4 ac
2a
t 1,2=−(−4)±√(−4)2−4 (1 ) (1 )
2 (1 )
t 1,2=4±√12
2
–
t 1,2=4±2√3
2
t 1,2=2±√3
t 1=2+√3 and t 2=2−√3
y l=c1 e(2+√3 ) t+c2 e
( 2−√3 ) t
yr=A3 t3+A2 t
2+A1t+A0
y 'r=3 A3 t2+2 A2t+A1
y ' 'r=6 A3 t+2 A2
y ' '−4 y '+ y=2t 3+3 t2−1
(6 A3t+2 A2 )−4 (3 A3 t2+2 A2 t+A1)+(A3 t
3+A2t2+A1t+A0 )=2 t3+3 t 2−1
A3 t3+(−12 A3+A2 )t 2+(6 A3−8 A2+A1 ) t+A1+A0=2 t3+3 t 2−1
Equation similarity:
A3=2
−12 A3+A2=3
−12(2)+A2=3
A2=27
6 A3−8 A2+A1=0
6 (2)−8(27)+A1=0
A1=204
A1+A0=−1
204+A0=−1
A0=−205
yr=2t 3+27 t 2+204 t−205
y= y l+ yr
y (t )=c1 e( 2+√3) t+c2 e
(2−√3) t+2 t 3+27 t2+204 t−205
y (0)=1
1=c1+c2−205
c1+c2=206 .........................(1)
y '(t )=(2+√3 ) c1e(2+√3) t+(2−√3 )c2 e
(2−√3) t+6 t2+54 t+204
y '(0)=1
1=( 2+√3 )c1+(2−√3 )c2+204
(2+√3 )c1+ (2−√3 )c2=−203 ........................... (2)
By using elimination and substitution method, the value of c1 and c2 can be obtained
from (1) and (2).
−203=(2+√3 )c1+( 2−√3 )c2........................... (2)
206=(2−√3 )c1+(2−√3 )c2 ...................................(1)
2√3 c1=−203−206 (2−√3 )
2√3 c1=−715+206√3
c1=−715√3+618
6
c1+c2=206
(−715√3+6186 )+c2=206
c2=715√3+618
6
y (t )=(−715√3+6186 )e (2+√3) t+(715√3+618
6 )e( 2−√3 )t+2 t3+27 t 2+204 t−205
TASK V (March 20th, 2014)
1.d2 xd t 2
+4dxdt
+8x=(20 t 2+16 t−78)e2 t
y(0)=y’(0)=0
2.d3qd t 3
−5d2qd t2
+25dqdt
−125q=(−500 t2+465 t−387)e2 t
q(0)=q’(0)= q’’(0)=0
Solution:
–
1.d2 xd t 2
+4dxdt
+8x=(20 t 2+16 t−78)e2 t
y(0)=y’(0)=0
quadratic equation is
λ2+4 λ+8=0
λ1,2=−b±√b2−4 ac
2a
λ1,2=−4±√42−4 (1)(8)
2(1)
λ1,2=−4±√−16
2
λ1,2=−2±2 i
y l=e−2t (c1cos 2t+c2 sin2 t)
yr=(A2t2+A1t+A0)e
2 t
y 'r=(2 A2t+A1 )e2 t+(A2t2+A1t+A0) (2e2 t )
y ' 'r=2 A2 e2 t+(2 A2 t+A1 ) ( 2e2 t )+( 2 A2t+A1 ) (2e2 t )+(A2 t
2+A1t+A0)( 4e2 t )
y ' '+4 y '+8 y=(20 t 2+16 t−78)e2t
2 A2 e2 t+( 2 A2t+A1 ) (2e2 t )+ (2 A2t+A1 ) (2e2 t )+(A2 t
2+A1t+A0 ) ( 4e2t )+4 {( 2 A2 t+A1 )e2 t+(A2 t2+A1 t+A0) (2e2 t )}+8 {(A2t
2+A1 t+A0)e2 t }=(20 t 2+16 t−78)e2 t
(2 A2+8 A1+20 A0 )e2 t+(16 A2+20 A1 ) t e2 t+(20 A2)t2e2 t=(20 t 2+16 t−78)e2t
20 A2=20
A2=1
16 A2+20 A1=16
16(1)+20 A1=16
20 A1=0
A1=0
2 A2+8 A1+20 A0=−78
2 (1 )+8 (0 )+20 A0=−78
20 A0=−78−2
20 A0=−80
A0=−4
yr=(t 2−4)e2 t
y = yl + yr
y (t )=e−2 t (c1cos 2t+c2sin 2 t )+(t 2−4)e2 t
y ' (t )=(−2e−2 t ) (c1 cos2 t+c2sin 2 t )+e−2t (−2c1 sin 2t+2c2cos2 t )+2 t e2 t+(t 2−4) (2e2 t )
y (0 )=0
0=c1−4
c1=4
y ' (0 )=0
0=−2c1+2c2−8
8=−2(4)+2c2
c2=8
y (t )=e−2 t (4cos 2t+8 sin 2 t )+(t2−4)e2t
2.d3qd t 3
−5d2qd t2
+25dqdt
−125q=(−500 t 2+465 t−387 )e2 t
q(0)=q’(0)= q’’(0)=0
Quadratic equation is:
λ3−5 λ2+25 λ−125=0
λ1=5 λ2=5 i
λ3=−5 i
y l=c1 e5 t+c2 cos5 t+c3 sin 5 t
yr=(A2t2+A1t+A0)e
2 t
y ' r=( 2 A2t+A1 )e2 t+(A2 t2+A1t+A0)(2e¿¿2 t)¿
¿2 A2t e2t+A1 e
2 t+2 A2 t2 e2 t+2 A1t e
2 t+2 A0e2 t
y ' 'r=2 A2 e2 t+8 A2t e
2 t+2 A1 e2 t+4 A2t e
2 t+4 A2t2e2 t+2 A1 e
2 t+4 A1 t e2 t+4 A0 e
2t
y ' ' ' r=12 A2e2 t+12 A1 e
2 t+8 A0 e2 t+24 A2t e
2 t+8 A1t e2 t+8 A2t
2 e2 t
y ' ' '−5 y ' '+25 y '−125 y=(−500 t 2+465 t−387 )e2 t
12 A2 e2 t+12 A1 e
2t+8 A0 e2 t+24 A2 t e
2t+8 A1 t e2t+8 A2 t
2 e2 t−5 {2 A2 e2 t+8 A2t e
2 t+2 A1e2 t+4 A2t e
2 t+4 A2t2e2 t+2 A1 e
2 t+4 A1 t e2 t+4 A0 e
2t }+25 {2 A2 t e2 t+A1 e
2t+2 A2t2 e2 t+2 A1 t e
2 t+2 A0 e2 t }−125 {(A2 t
2+A1t+A0 )e2 t }=(−500 t 2+465 t−387 )e2 t
(2 A2+17 A1−87 A0 )e2t+ (34 A2−87 A1 ) t e2 t+(−87 A2) t 2 e2 t=−500 t2 e2t+465 t e2 t−387e2t
−87 A2=−500
A2=50087
34 A2−87 A1=465
34 (50087 )−87 A1=465
A1=−23455
7569
2 A2+17 A1−87 A0=−387
2( 50087 )+17 (−23455
7569 )−87 A0=−387
A0=2617468658503
yr=( 50087t 2−23455
7569t+ 2617468
658503 )e2 t
y= y l+ yr
y (t )=c1e5 t+c2 cos5 t+c3sin 5 t+( 500
87t 2−23455
7569t+ 2617468
658503 )e2 t
y ' (t)=5 c1 e5t−5c2 sin5 t+5c3cos 5t+( 1000
87t−23455
7569 )e2 t+(50087t 2−23455
7569t+ 2617468
658503 ) (2e2 t )
y ' ' (t )=25c1 e5 t−25c2cos 5t−25c3 sin 5 t+ 1000
87e2 t+(1000
87t−23455
7569 )( 2e2 t )+( 100087
t−234557569 ) (2e2 t )+( 500
87t 2−23455
7569t+ 2617468
658503 ) (4 e2 t )
y (0 )=0
0=c1+c2+2617468658503
c1+c2=−2617468
658503 ................................... (1)
y ' (0 )=0
0=5c1+5c3−234557569
+5234936658503
5c1+5c3=−3194351
658503
c1+c3=−31943513292515
.................................... (2)
y ' ' (0 )=0
0=25c1−25c2+1000
87−46910
7569− 46910
7569+ 10469872
658503
25c1−25c2=−9876532
658503 .................................... (3)
25c1+25c2=−65436700
658503 ................................... (1)
50c1=−75313232
658503
c1=−7531323232925150
From equation (1), we get the value of c2.
c2=−2617468
658503+75313232
32925150
c2=−5556016832925150
From equation (2), we get the value of c3.
c3=−31943513292515
+ 7531323232925150
c3=4336972232925150
+
y (t )=−7531323232925150
e5 t−5556016832925150
cos5 t+ 4336972232925150
sin 5 t+( 50087t 2−23455
7569t+ 2617468
658503 )e2 t