Find the area of the surface obtained by rotating the curve(adsbygoogle = window.adsbygoogle || []).push({});

y=2e^(2y)

from y=0 to y=4 about the y-axis.

Any help on this would be greatly appreciated. This has my whole hall stumped. We know that you have to use the equation 2pi*int(g(y)sqrt(1+(derivative of function)^2), but cannot figure out how to integrate this correctly.

What I have gotten so far:

y=2e^(2y)

[when u=2y, du/2=dx]

y=e^u

New bounds: 1 to e^4

2pi*int(e^u*sqrt(1+(e^u)^2)

How do you go from there? Any help would be greatly appreciated.

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# Homework Help: Find Surface Area obtained by rotating a curve?

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