The Attempt at a SolutionSolution to Integral using Leibniz Rule & IB Parts

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Homework Statement



Using Leibniz rule and integration by parts, solve \frac{\partial}{\partial x} \int_0^y u dy.

Homework Equations



u = U(x) f' (\eta)

\eta = \eta(x,y) = y g(x)
 
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Dkie said:

Homework Statement



Using Leibniz rule and integration by parts, solve
\frac{\partial}{\partial x} \int_0^y u dy.

You need to enclose your tex in tex tags (without the space) [ tex]...[/tex].

Is perchance that dy supposed to be dx? And if so, what have you tried?
 
In particular is u a function of both x and y?

I don't see any need for "integration by parts". Leibniz' rule says
\frac{d}{dx}\int_{\alpha(x)}^{\beta(x)} f(x,y)dy= \frac{d\beta}{dx}f(x,\beta(x))- \frac{d\alpha}{dx}f(x,\alpha(x))+ \int_{\alpha(x)}^{\beta(x)} \frac{\partial f}{\partial x}dy

So whether the derivative is with respect to x or y, that should be enough.
(Unless u is some special function you didn't mention.)
 
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