Are the following functions monotonic? If the function is monotonic, is the function is increasing, strictly increasing, decreasing or srictly decreasing? Justify your answer. a.) f1 : R - R, X - - X 1+x-1) b.) f2: (0, 4) - Rx 4 - x, when x 5 2 0, when x > 2 c.) Let f: (0, 1) - (0, 1) be a strictly decreasing bijection. Prove that the inverse function f -1: (0, 1) - (0, 1) of the function f is strictly decreasing