Calculate the derivative of the function 3x 9 4x 1 s x Step 1 Recall the Chain Rule If f is a differentiable function of u and u is a differentiable function of x then the composite f u is a Many like to think of the derivative of f expression as the derivative of f of the expression times the 3x 9 4x For the function s x the derivative of s If we think of 3x 9 4x 1 note that s is a composite function with an expression that is rais as u then u is a differentiable function of x and u Apply the Generalized Power Rule to find the derivative of u f x 3x 9 4x1