3 y = f(x) on [0,4] 0 0 400 400 4 0.9 0.9 0 0 0 0 1 1 0 1 55 0 65 1 1 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0.9 0.9 0 0 0 0 1 1 0 1 0 0 0 0 0