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\textbf{Partial Differentiation}

\textit{\textbf{Functions of more than one variable}}
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\textbf{Question}

Sketch the graph of the function.

$$ f(x,y) = y^2, \ \ \ (-1 \le x \le 1, \ -1 \le y \le 1)$$


\textbf{Answer}

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\epsfig{file=PD-1A-3.eps, width=50mm}
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