(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I'm not even going to get to the real problem. I'm just having a basic mental block with how to do the substitution. I just need to know how to convert this ODE into terms of [tex]z[/tex]

2. Relevant equations

[tex]x^2y''+xy'+4(x^4-1)y = 0[/tex]

[tex]x^2 = z[/tex]

3. The attempt at a solution

I have some vague idea. I think I'm supposed to use the chain rule. This is rather embarrassing in the first place.

[tex]\frac{dy}{dx} = \frac{dy}{dz}\frac{dz}{dx}[/tex]

I don't know where to go from here. I've been looking around at some of the chain rule instructions that are out there online, but I have not been able to link it to what I need to do here. In fact, the chain rule in general has been a large weakness for me, and I'm surprised that I have gotten to graduate classes and am still mixing it up so frequently.

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# Homework Help: VERY simple question regarding substitution

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