Horrible expression involving logs and inverse tan functions

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SUMMARY

The discussion centers on solving the ordinary differential equation (ODE) given by \(\frac{d^2y}{dx^2} + (y^4-1)\frac{dy}{dx} = 0\). The initial attempt at a solution leads to the expression \(\frac{dy}{dx} = (1 - y^4)\), which is then integrated incorrectly, resulting in a complex expression involving logarithms and inverse tangent functions. Participants emphasize the importance of correctly accounting for the dependence of \(x\) on \(y\) during integration to ensure the solution aligns with the original equation.

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Homework Statement



\frac{d^2y}{dx^2} + (y^4-1)\frac{dy}{dx} = 0



Homework Equations



\frac{dy}{dx} + (y^4-1) = 0



The Attempt at a Solution



\frac{dy}{dx} = (1- y^4)
\frac{dy}{1- y^4} = dx

Then I get a horrible expression involving logs and inverse tan functions on the LHS and x + A on RHS ?

sorry heading should be ODE not PDE
 
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You have the wrong expression after the integration, try taking the derivative of that with respect to x to see if you get the same expression as you started with. HINT: You forgot the x to y dependence.
 

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