Use the result of Exercise 21 to show that the following functions are differentiable at x = 0.

Data from in Exercise 21

Suppose that the functions ƒ and g are defined throughout an open interval containing the point x₀, that ƒ is differentiable at x₀, that ƒ(x₀) = 0, and that g is continuous at x₀. Show that the productƒg is differentiable at x₀. This process shows, for example, that although 0 x 0 is not differentiable at x = 0, the product x 0 x 0 is differentiable at x = 0.