Consider f(z) = 'i'sin2 z 14 cosz on [0, 271']. Determine the intervals on which f is concave down. (9 f is down :i O f is concave down nowhere. Determine the intervals on which 1' is concave up. f is concave up on: :] O f is concave up nowhere. Determine the value and location of any inflection point of 3'. Enter the solution in (z, f(z)) form. If multiple solutions exist, use a comma-separated list to enter the solutions. f has an inflection point at: C] O f has no inflection point