*12. Consider the shaded region bounded by the sine and cosine functions depicted below. y = cos x 0.5- -0.5 y = sin x 0.5 1 * -0.5+ Use the washer method to find the volume of the solid of revolution formed by revolving the shaded region around the x-axis. Hint: Recall the trigonometric identity cos x-sin x = cos(2x). Take special care in finding the upper limit of integration.