Differential Equations initial value problem

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The discussion focuses on solving the initial value problem defined by the equation 2t(dy/dt) + y = t^4 with the condition f(0) = 0. Participants express difficulty in using separation of variables and seek clarification on applying an integrating factor. The equation can be rewritten in a linear form, allowing for the use of an integrating factor to simplify the solution process. Suggestions include exploring clever substitutions or recognizing the left-hand side as a derivative. The conversation emphasizes the importance of finding an appropriate integrating factor for solving the differential equation effectively.
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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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Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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