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QUESTION

A curve is defined parametrically by $x=\sin t$ and $y=\cos t$.
Find $\frac{dy}{dx}$ in terms of $t$.

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ANSWER

$\ds\frac{dy}{dx}=\frac{\frac{dy}{dt}}{\frac{dx}{dt}}=\frac{-\sin
t}{\cos t}=-\tan t$





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