Using the chain rule for derivative: Suppose that we have two functions f ( x ) {\displaystyle f(x)} and g ( x ) {\displaystyle g(x)} and they are both differentiable, If we define F ( x ) = ( f ∘ g ) ( x ) {\displaystyle F(x)=(f\circ g)(x)} , then the derivative of F ( x ) {\displaystyle F(x)} is f ′ ( g ( x ) ) g ′ ( x ) {\displaystyle f'(g(x))g'(x)} .
