Consider the region in the plane bounded by ,

MATHEMATICS · Subjective · AP · Calculus AB · Applications of Integration · Applications of Integration

Problem

Consider the region in the plane bounded by

y=\sin x

y=0

, and

x=\pi

. Another curve,

y=\cos x

, lies above the region throughout this interval. When the bounded region is revolved about the

x

-axis, which function—

y=\sin x

y=0

—determines the outer radius of each washer, and why? Provide a brief justification.