# GATE2013-18

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

1. $e^x+e^y$
2. $e^x-e^y$
3. $\frac{1}{e^x+e^y}$
4. $1$
in Calculus
recategorized

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