By using Laplace transforms, solve the following differential equations subject to the given initial conditions. y"-4y'=-4te^{2t}, y_0=0, y'_0 =1 y"+2y'+10y=-6e^{-t}sin3t, y_0=0, y'_0=1

he298c

he298c

Answered question

2021-02-15

By using Laplace transforms, solve the following differential equations subject to the given initial conditions. 
y"-4y'=-4te2t,y0=0,y'0=1

y"+2y'+10y=-6e-t sin3t,y0=0,y'0=1

Answer & Explanation

firmablogF

firmablogF

Skilled2021-02-16Added 92 answers

Step 1The given differential equation is,
y"4y=4te2t
where y0=0,y0=1
Take the Laplace Transform on both sides,
L(y4y)=L(4te2t)
L(y)4L(y)=4L(te2t)
Consider the formulae,
L(y)=s2L(y)sy0y0
L(y)=sL(y)y0
L(te2t)=1(s2)2
Step 2
Substitute the values,
L(y)4L(y)=4L(te2t)
s2L(y)sy0y04[sL(y)y0]=41(s2)2
s2L(y)s(0)(1)4sL(y)=(4)(s2)2
L(y)[s24s]=1+(4)(s2)2
L(y)=s24s+44(s2)2(s24s)
L(y)=1(s2)2
Step 3
Take the Inverse Laplace Transform both sides,
L1[L(y)]=L1[1(s2)2]
y=L1[1(s2)2]
y=te2t
Thus, the solution of the given integral is y=te2tii)
The given differential equation is,
y+24y+10y=6etsin3t
where y0=0,y0=1
Step 4
Take the Laplace Transform on both sides,
L(y+24y+10y)=L[6etsin(3t)]
L(y)+24L(y)+10L(y)=6L[etsin(3t)]
Use the same formulae as mentioned above,
s2L(y)01+2[sL(y)0]+10L(y)=(6)3(s+1)2+9
s2L(y)1+2sL(y)+10L(y)=18s2+2s+1+9
[s2+2s+10]L(y)=118s2+2s+10
L(y)=s2+2s+1018(s2+2s+10)2
L(y)=s2+2s-8(s2+2s+10)2

Step 5

Take the Inverse Laplace Transform both sides, 
L-1[L(y)]=L-1s2+2s-8(s2+2s+10)2

y=te-tcos(3t)

Thus, the solution of the given differential equation is y=te-tcos(3t)

Do you have a similar question?

Recalculate according to your conditions!

New Questions in Differential Equations

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?