Determine the open intervals on which the graph is concave upward or concave downward. (Enter your answers using interval notation. If an answer does not exist, enter DNE.) f(x) = x2 - 3x + 9 concave upward concave downwardDetermine the open intervals on which the graph is concave upward or concave downward. (Enter your answers using interval notation. If an answer does not exist, enter DNE.) x - 8 f( x) = - 7x + 4 concave upward concave downwardDetermine the open intervals on which the graph is concave upward or concave downward. (Enter your answers using interval notation. If an answer does not exist, enter DNE.) y = 8x - 7 tan x, J' concave upward concave downwardFind the point of inflection of the graph of the function. (If an answer does not exist, enter DNE.) f(x) = xV6 - x (x, y) = Describe the concavity. (Enter your answers using interval notation. If an answer does not exist, enter DNE.) concave upward concave downwardFind all relative extrema of the function. Use the Second Derivative Test where applicable. (If an answer does not exist, enter DNE.) x) - xe '4\" relative minimum (x, y) - relative maximum (x, y} - (E) (E)