Differential equations - backwards problem

  • #1
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1
OP warned about not including efforts

Homework Statement


If y=y(t) is the solution of the initial value problem

{
y'+(2t+1)y=2cos(t)

y(0)=2

then

y''(0)=?

it is a multiple choice practice problem with choices

y''(0)=2
y''(0)=-2
y''(0)=4
y''(0)=0
y''(0)=-4


Homework Equations




The Attempt at a Solution



Im really not sure how to go about solving this.

When I try to solve for y(t) i get a huge mess.
 

Answers and Replies

  • #3
Simon Bridge
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Find an expression that has y''(t) in it.
[edit]... of LCKurtz link: that's interesting: someone in your class?
 
  • #4
LCKurtz
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Find an expression that has y''(t) in it.
[edit]... of LCKurtz link: that's interesting: someone in your class?

?? Who are you addressing? Me? Not one of my classes. I retired over 10 years ago.
 
  • #5
Ray Vickson
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Homework Statement


If y=y(t) is the solution of the initial value problem

{
y'+(2t+1)y=2cos(t)

y(0)=2

then

y''(0)=?

it is a multiple choice practice problem with choices

y''(0)=2
y''(0)=-2
y''(0)=4
y''(0)=0
y''(0)=-4


Homework Equations




The Attempt at a Solution



Im really not sure how to go about solving this.

When I try to solve for y(t) i get a huge mess.

Why solve at all? You have ##y'(t) = 2 \cos(t) - (2t +1) y(t)##, so you can get ##y''(t)##.
 

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