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Suppose $y=1$ and $y=xlnx$ are solutions to some second-order homogenous differential equation. Construct the equation.

Edit #1: OK, the Wronskian gives $lnx+1$ but I don't see how this helps me.

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I would recommend that you show some work. It sounds like you are assigning us homework. –  Jebruho Nov 5 '12 at 4:23
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think about the Wronskian. –  James S. Cook Nov 5 '12 at 4:25
    
Since you are new to this site, please consider reading this: How to ask a homework question?. In particular, you should use homework tag if your question comes from a homework; people will still help, so don't worry. I wrote this comment because the question sounds homework-like. –  Rahul Nov 5 '12 at 5:17

1 Answer 1

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I assume you want a 2nd order homogeneous linear equation, which is to say, you want functions $a(x),b(x),c(x)$ such that $$a(x)y''+b(x)y'+c(x)y=0$$ identically. So, put in $y=1$, and you get an equation relating $a,b,c$. Put in $y=x\log x$, and you get another equation relating $a,b,c$. Now find $a,b,c$ satisfying those two equations.

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