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ACLerok
Sep15-04, 09:05 PM
i'm told to use the method of cylindrical shells to find the volume gnerated by rotating the region bounded these curves about the y axis:
y=e^(-x^2)
y=0
x=0
x=1
Couple questions. What does the graph of y=e^(-x^2) look like? Also, i know the integral is =integral(a,b) 2(pi)x*e^(-x^2) how do i evaulate the e^(-x^2) part?

HallsofIvy
Sep15-04, 09:10 PM
The graph of e-x^2 is the famous "Bell shaped curve"!

As far as the integral of x e-x^2 is concerned, try the substitution u= -x^2.