Let f(x) =  and graph the function f(f(x)) in the window [−15, 15] by [−10, 10]. Trace to...

Let f(x) =  and graph the function f(f(x)) in the window [−15, 15] by [−10, 10]. Trace to examine the coordinates of several points on the graph and then determine the formula for f(f(x)).