# 3.4 | The Chain Rule

The Chain Rule:
If $$g$$ is differentiable at $$x$$ and $$f$$ is differentiable at $$g(x)$$ then $$f(g(x))$$ is differentiable at $$x$$ and
$$\frac{d}{dx}[f(g(x))] = f'(g(x))g'(x).$$