y' = 2y/x + x cos (y/x^2), with y=z*x^2(adsbygoogle = window.adsbygoogle || []).push({});

=> y' = 2zx + x cos z

and y=z*x^2 => y' = 2zx + x^2 * dz/dx

So that leaves x^2 * dz/dx = x cos z => dz/cos z = dx/x

I integrate both sides so that:

sec z + tan z = x + C

But I don't have a clue on how to get past that point. Should I start from the beginning with another technique to avoid getting sec z + tan z?

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# Homework Help: A diff. eq. or trigonometry related problem?

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