I keep getting stuck on one part of the equation. can somebody help?(adsbygoogle = window.adsbygoogle || []).push({});

dy/dx = y(xy^{3}- 1)

dy/dx = xy^{4}- y

dy/dx + y = xy^{4}

u = y^{1-n}= y^{-3}

y = u^{-3}

dy/dx = dy/du * du/dx

dy/dx = -3u^{-4}du/dx

Substituting terms into the original equation

-3u^{-4}du/dx + u^{-3}= x(u^{-3})^{4}

Here is where I get stuck. When I divide u^{-4}to clean up the equation, the right hand side still has u^{-8}remaining. I will not be able to go on since the right hand side can only have x terms. What am I doing wrong?

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# Homework Help: Bernoulli Differential Equation?

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