Differential equations - backwards problem

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dmoney123
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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.
 
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Simon Bridge said:
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.
 
dmoney123 said:

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)##.