I need help with these two questions and if you could explain them to me step by step please and thank you .

99. Let f(x) x2 + 1 a. Show that f is continuous for all values of x. b. Show that J () is nonnegative for all values of a. c. Show that f has a zero at x = 0. Does this contradict Theorem 5? 100. Let f(x) = x - V1 -x2. a. Shows that f is continuous for all values of a in the interval [-1, 1]. b. Show that f has at least one zero in [-1, 1]. c. Find the zeros of f in [-1, 1] by solving the equation f (x) = 0