Question

The region enclosed by the graph e^(x/2), y=1, and x=ln(3) is revolved around the x-axis. Find the volume of the solid generated.

I don't understand if we have to use the washer method or the disk method for this one because when I drew it out on a graph it looked very confusing.

Answer 1

would it help to do this...in order to decide the method.
What if you were going to find the volume between e^(x/2), x=0 to x=ln(3), then subtract out the volume from x=0 to x=ln(3) between y=0 and y=1 (volume subtracted would be 2PI*1^2*ln(3). After subtracting out this cylinder, you are left with the original problem.