I need help calculus 2

[hurdler]

Consider solid obtained by rotating the region bounded by the given curves y=lnx y=3 y=6 x=0 about the y-axis, find the volume of this solid

 

[Deleted member 4993]

Consider solid obtained by rotating the region bounded by the given curves y=lnx y=3 y=6 x=0 about the y-axis, find the volume of this solid

Draw a sketch of the problem and determine the limits. Decide whether to use disk method or washer method.

Please show us your work, indicating exactly where you are stuck - so that we know where to begin to help you.

 

[galactus]

HINT: It will be easier if you integrate in terms of y and use washers.

 

[hurdler]

I know how to set up the graph and reflect the image but I'm not sure what the washer will look like

 

[BigGlenntheHeavy]

Not a washer, but a disc, observe:

\(\displaystyle \pi \int_{3}^{6}(e^{y})^{2}dy \ = \ 255,021 \ cu. \ units.\)

Look at graph for further elucidation.

[attachment=0:791p2zft]xxx.jpg[/attachment:791p2zft]