Leibniz Notation

A different way of writing derivatives. It’s very useful for parametric functions.

$\frac{d y}{d x}$ is read as “the first derivative of y with respect to x” and is equivalent to $f^{'} (x)$ .

3.6 - The Chain Rule

If $y = f (u)$ and $u = g (x)$ , then $\frac{d y}{d x} = \frac{d y}{d u} \cdot \frac{d u}{d x}$ where $\frac{d y}{d u}$ is evaluated at $u = g (x)$ .