For each function determine i the critical values ii the intervals of increasing or decreasing iii the maximum and minimum points a f x 4x 12x 7 b f x x 9x 24x 10 x 2 x 2x 15 c y 1 Find the intervals of concavity for the function and state the points of inflectio a f x x 2x x 2 x x 4 b f x