Omnimaga

General Discussion => Other Discussions => Math and Science => Topic started by: Yeong on August 31, 2012, 03:04:13 pm

Title: Volume of rotating graphs help
Post by: Yeong on August 31, 2012, 03:04:13 pm
I don't know if I'm having a brainfart or something, but the online homework says it's wrong. Did I really do it wrong?
Here's the graph, and I rotate the region bounded by Y1 and Y2 by Y3(Y=2).

(http://img.removedfromgame.com/imgs/08-31-2012%20Image001.jpg)

So I did this (I'm putting pi later so don't worry about that)

(http://img.removedfromgame.com/imgs/08-31-2012%20Image003.jpg)
EDIT: Even though it says x, it's y.

so (at least in my opinion) answer should be 1.75161*pi, but the online homework is keep saying that it's wrong. D:

EDIT: problem solved. I forgot to solve graph for Y. :\