3:33 . - 35 PS Express APPLICATION 6. If f(x) = x' -3x2 -1, at what x-values will inflection points occur? [3] 7. Consider the function f(x) = x3-3x + 4x . Determine the interval(s) on which the graph is concave up and the interval(s) in which it is concave down. [8] 8. Find "c" given that the graph of f (x) = cx2 - - has a point of inflection at x=4.[4] THINKING 9. Determine if the function y Itsine+2ncos0 is a solution to the differential equation y"ty=0. [5] 10. Sketch g (x) = 6x2-2 x3 [10]