Find the area under the curve y = sin(2x) + cos(x) between 0 and pi/2

to find the area integrate the function between 0 and pi/2:

indefinite integral of y = -1/2 cos(2x) + sin(x) + c

ignore c and input boundary conditions:

[-1/2 cos(pi) + sin(pi/2)] - [-1/2 cos(0) + sin(0)] = [1/2 + 1] - [-1/2 + 0] = 2