Question

Use the graph of the function to andeor the follewing. x) cos(x) on the interval [-2, 2] (a) Find the x-intercepts of the graph of y x). (Enter your answers as a comma separated Sst) (b) Rnd they İntercepts of the graph of y-nr), (Enter your Dewers as a comm,separated 12) on which the grap of increasing and the intervals on which the graph af yo is decreasing. (Enter your answers using interval netatien J ncreasing )x decreasing 1-.) x 帽。다自e

Answer 1

y = cos x in [-2 pi, pi]. For x - intercept, put y = 0 = > cos x = 0 x = cos^-1 (0) therefore x - intercepts are pi/2, 3 pi/2 To find y - intercepts, put x = 0 = > y = cos (0) = 1 therefore y intercept is 1. y = f (x) is increasing in the intervals, (-2 pi, -3pi/2), (-pi/2, pi/2) , (3 pi/2, 2 pi) & decreasing on, (-3 pi/2, -pi/2) , (pi/2, 3 pi/2).