Differential Equations initial value problem

hocuspocus102
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Homework Statement



Let f(t) be the solution to the initial value problem 2t(dy/dt)+y=t^4
with f(0) = 0
find f(t).

Homework Equations





The Attempt at a Solution



I tried to do this by separating variables but that hasn't gotten me very far. I don't know if I can do it by doing that thing where you find an integrating factor and like raising e^(some integral)? It didn't really make any sense to me when I tried it, so could someone explain it please? Thanks!
 
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Or a cleaver substitution? Something of the form t^\alpha y with some handy value of \alpha? Does not the left hand side of your equation look like a derivative of a something?
 
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Because it is a linear equation, there is a formula for the "integrating factor". Write it as dy/dx+ y/2t= (1/2)t^3.

Now look for u(t) such that d(uy)/dt= u (dy/dt)+ (du/dt)y= u dy/dt+ (u/2t)y
 
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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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