Math 1312
D.Wilson
Section 7.2: More on the Disk/Washer Method
1. Sketch the region bounded by the graphs of the functions. Then find the volume of
the solid generated when the region is rotated about the indicated axis.
(a) f(x) = −x2+ 4x+ 1 and g(x) = x+ 1.Rotate about the x-axis.
(b) y=sin(2x), y = 0, x = 0, x =π
4.Rotate about the x-axis.
(c) Rotate the region from part (b) about the line y= 2.
(d) xy = 6, y = 2, y = 6,and x= 0.Rotate about the line x= 6.
Homework due in class on Tuesday, January 19
•Section 7.1: #19, 26, 32, 47, 67 (redo)
•Section 7.2: #3, 6, 9, 10, 20, 21, 24, 26, 29, 32, 33, 36