Find all the critical numbers of f x 2x 18 then determine the local minimum and maximum points by using a graph O O O Critical numbers x 3 and x 3 There is no local maximum or local minimum Critical numbers x 3 x 0 and x 3 0 3 18 is a local minimum Critical numbers x 0 and x 3 0 18 is a local minimum Critical number x 0 0 3 18 is a local and minimum