First integral/general integral

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Homework Statement


Find general integral of {(y+z)Z_x+yZ_y=x-y}

Homework Equations


{pZ_x+qZ_y=r}
{f(u_1,u_2)=0} (u1 and u2 are first integrals, this is the definition of a general integral)

The Attempt at a Solution


I identified p=x+z, q=y and r=x-y, I'm thinking I might have to do something with integral curves to find the first integrals, but I don't how I would do that.

Thanks for any help!
 
Last edited:
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Had a brain fart when I asked this haha, forgot that {dx/p=dy/q=dz/r} (posted this just incase someone googles a similar problem and sees this thread).
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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