# Math Help - using cylindrical shells

1. ## using cylindrical shells

ok im not sure where i went wrong, but im getting a negative answer for volume which cant be right...any thoughts? thanks in advance...IMG.pdf

2. ok i redid the problem and got an answer of 84 pi, can someone check my answer to see if they got the same thing. i apologize i was tired when i did this problem last night. haha im much better now. :O) thanks in advance!

so again my final answer was 84 pi can anyone confirm? thanks