Determine the intervals on which the given function is concave up or concave down and find the points of inflection. f(x) = (x – 12)(1 – x³) - (Use symbolic notation and fractions where needed. Give your answer as a comma separated list of points in the form in the form (*, *). Enter DNE if there are no points of inflection.) points of inflection: (x, y) = (Use symbolic notation and fractions where needed. Give your answers as intervals in the form (*, *). Use the symbol oo for infinity, U for combining intervals, and an appropriate type of parenthesis "(", ")", "[", or "]", depending on whether the interval is open or closed. Enter Ø if the interval is empty.) f is concave up when x E f is concave down when x E