In the book I'm reading it says here that the derivative of a constant times a function equals the constant times the derivative of the function. It gives the equation f(x)=c*u(x), then f '(x)=c*u'(x) Where f(x) and u(x) are functions of x. So if f(x)=5x^2, thats 10x. I understand how to do these problems, they're easy, but then my book says If f(x)=cx^n, then f '(x)=cnx^n-1 It says this example is a special case of a constant times a function. I'm confused here. For whatever reason I'm thinking that these two would equal the same thing if used with the same variables? Could somebody tell me what my book means when it says this?