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Tom Mattson
Oct24-04, 04:41 PM
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Quote Quote by willib
wouldent that be the integral from -infinity to infinity of 1/Y dx..
since you are revolving around the x axis...
No, the formula for the surface area is S=2π∫r(x)[1+(f'(x))2]dx.


The integral is pretty easy if you do it by parts. Start from:


and let u=(1+x4)1/2 and dv=dx/x3.