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\begin{center}
\textbf{Partial Differentiation}

\textit{\textbf{Limits}}
\end{center}

\textbf{Question}

Evaluate the given limit. If the limit does not
exist, explain why.

$$\lim_{(x,y)\to(0,0)} \frac{\sin (x-y)}{\cos (x+y)}$$


\textbf{Answer}

$\ds \lim_{(x,y)\to(0,0)} \frac{\sin (x-y)}{\cos (x+y)}=\frac{\sin
0}{\cos )}=0$


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