Existence, Uniqueness of a 1st Order Linear ODE

royblaze
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Homework Statement



Solve the Cauchy problem:

(t2 + 1)y' + etsin(t) y = sin(t) t2
y(0) = 0

Homework Equations



y'(t,y) + p(t)y = g(t,y)

Integrating factor e(integral of p(t))

The Attempt at a Solution



I tried finding an integrating factor, but it came out ugly. I couldn't solve the integral.

e(integral of) (et * sin(t)) / (t2 + 1)

Then I tried separating, and it didn't work out too nice either. I was considering using those psi things (as in, an exact equation approach) to find an answer, but the homework topics do not involve those. Instead, the topics are Existence and Uniqueness, Autonomous Eqns, Modeling with 1st Order ODEs.

So how do I even start this question??
 
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Upon reading my notes, perhaps we have not yet covered the strategy required to attack this problem? Any help is appreciated regardless.
 
I don't think you will find any standard method to solve that. Most DE's aren't exactly solvable by elementary functions and that looks like a good candidate.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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