Question

Find $\frac{dy}{dx}$ when $x^2+y^2=c^2$.

Answer 1

Given,

$x^2+y^2=c^2$

Now, differentiating both sides with respect to $x$ we get,

$2x+2y\frac{dy}{dx}=0$

or, $\frac{dy}{dx}=-\frac{x}{y}$