y=sqrt(x+1),x=1,y=-1

i have to find a volume(certain integral) of geometric body which is showed (produced) by y=sqrt(x+1) rotation about y=-1...Attachment 27599

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- Mar 19th 2013, 11:00 AMmathe26integral 1
y=sqrt(x+1),x=1,y=-1

i have to find a volume(certain integral) of geometric body which is showed (produced) by y=sqrt(x+1) rotation about y=-1...Attachment 27599 - Mar 19th 2013, 11:33 AMTheEmptySetRe: integral 1
The radius (or distance) between the functions and the line y=-1 is

$\displaystyle r=\sqrt{x+1}-(-1) \implies r=\sqrt{x+1}+1$

Now to find the volume of the solid of rotation use the disk method

$\displaystyle \int_{-1}^1 \pi r^2dx=\int_{-1}^1 \pi (\sqrt{x+1}+1)^2dx$ - Mar 19th 2013, 11:39 AMmathe26Re: integral 1
sorry but i do not know to continue,can u help a little bit more :)