Module 8 : Applications of Integration - II
Lecture 24 : Volume of solids of revolution by washer method [Section 24.1]
(ii)
 Let be the region in the first quadrant above the curve and below the curve recovered around
 
 

Note that to apply the washer method, we have to split the solid in two pieces: for and . Thus, the required volume is given by

.

  Visualizations of volume by washer method
   
 

PRACTICE EXERCISES
1.
 Find the volume of the solid when the region enclosed by given curves is revolved about .
(i)
(ii)
(iii)
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