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\textbf{Partial Differentiation}

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

Sketch the level curves of the function.

$$ f(x,y)= \frac{y}{x^2+y^2}$$


\textbf{Answer}

This is a a family of circles that pass through the origin, with the
circles centred on the $y$-axis. Although the origin is not on any of
the level curves.

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