Variation of Parameters problem

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pergradus
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Homework Statement



Find a particular solution by method of variation of parameters:

t2y'' - 2y = 3t2 - 1

given:

y1 = t2
y2 = t-1

Homework Equations



img9.gif


The Attempt at a Solution



I get [tex]Y(t) = t^2ln(t) - \frac{1}{3}t^2 + \frac{1}{2}[/tex]

The book gives [tex]Y(t) = t^2ln(t) + \frac{1}{2}[/tex]

I don't understand why they are off by the 1 term?
 
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HallsofIvy said:
The only thing I can tell you is that they aren't off by one term- you are!

And since you don't show any work, we can't say why you are. I suspect you have an error in your second integral.

By "they" I was referring to the the two answers - mine and theirs.

And I made no mistakes in the integration - check my work if you want. This is the THIRD time I've done this problem and I get the same answer.

It will take me hours to type this in LaTex so please just look at picture I uploaded. The -1/3t2 term just doesn't go away.
 

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