For the region in the xy-plane bounded above by and below by on the interval

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

Problem

For the region in the xy-plane bounded above by

y = 7 - x^{2}

and below by

y = 3 - x^{2}

on the interval

-1 \le x \le 1

, the region is revolved about the horizontal line

y = 1

. Which of the two bounding functions determines the smaller radius of any washer generated by the revolution? Briefly justify your answer.