Now we must find f x which is given by the general antiderivative of f x 18x2 C We note that f x is the sum of two functions h x 18x and b x C such that f x h x b x This means that f x will be given by the following where H x is the general antiderivative of h x B x is the general antiderivative of b x and D is an arbitrary constant f x H x B x D Furthermore we note that h x 18x2 is the product of a constant and a function k x x such that h x 18k x Finally we note that b x C is a constant function and can be written in the form b x Cx Applying the formulas described in this step and those used in the previous step we can now state the following letting D represent the arbitrary constant Do not add any additional constants f x 18x C 18 f x 18 Cx D To conclude give an equation for f Use C for the constant of the first antiderivative and D for the constant of the second antiderivative f x