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QUESTION

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