Is this differential exact or not?

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Homework Statement


Is the differential 3x^2y^3dx+3x^3y^2dy exact or not?
Please show me how to do this problem using Euler's criterion.

Homework Equations





The Attempt at a Solution


Euler says if partial deriv of first term = partial deriv of 2nd term then it must be exact right?
 
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jenzao said:

Homework Statement


Is the differential 3x^2y^3dx+3x^3y^2dy exact or not?
Please show me how to do this problem using Euler's criterion.

Homework Equations





The Attempt at a Solution


Euler says if partial deriv of first term = partial deriv of 2nd term then it must be exact right?

To be exact; the partial derivative with respect to y of the first term (the one proportional to dx) must be equal to the partial derivative with respect to x of the second term.
 
Yes it appears to be exact. Now all you need to do is to find the potential function.
 
Or, more mathematically, find the anti-derivative. "Potential function" is physics terminology.
 
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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