Question

Which of the following graphs represents the function y = 2 cos(x – π∕2) – 1?

Answer 1

B

Explanation:

maximum value is reached if cos (x-π/2) = 1, so the maximum value y = 2-1 = 1

minimum value is reached if cos (x-π/2) = -1, so the minimum value y = -2-1 = -3