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Consider the following. F( x ) = 4 1 3-3x2 Find the critical numbers. (Enter your answers as a comma-separated list. If an answer does not exist, enter DNE.) X = 0,3, - 2 Find the open intervals on which the function is increasing or decreasing. Use a graphing utility to verify your results. (Enter your answers using interval notation. If an answer does not exist, enter DNE.) increasing (-2,0), (3,00) decreasing (0,3), (-00, - 2)