differentiation

Related Questions

• If $u=\log ({{x}^{2}}+{{y}^{2}}),$ then $\frac{{{\partial }^{2}}u}{\partial {{x}^{2}}}+\frac{{{\partial }^{2}}u}{\partial {{y}^{2}}}=$

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• $(x - y){e^{x/(x - y)}} = k$ then

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• $\frac{d}{{dx}}\left( {{x^3}{{\tan }^2}\frac{x}{2}} \right)$=

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• If $u=x{{y}^{2}}{{\tan }^{-1}}\left( \frac{y}{x} \right)$, then $x{{u}_{x}}+y{{u}_{y}}=$

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• If $A+B=\frac{\pi }{2},$ the maximum value of $\cos A\cos B$ is

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