(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement.

Two 2nd order ODEs are given as :

x''-2xy''+x^2 y' = 0

x"+y"+xy'+yx'=0

write a code to solve them numerically using RK4 in matlab.

3. The attempt at a solution

I have some idea of starting this kind of problem. That is, I first need to convert them into Four 1st order ODEs. I began this by:

let p=x' and q=y'

So, p'=x" and q'=y"

put these in original eqn, I got

p'-2xq'+x^2 q = 0

p'+q'+xp+yq = 0

What should I do now? Is my approach correct? I didn't get Four Eqns as I expected!

PLEASE HELP

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# Homework Help: TWO 2nd order coupled DEs

Can you offer guidance or do you also need help?

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