Surface area of sin(x) rotated about the x-axis

Thread starter emc92
Start date Feb 21, 2012
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Area Surface Surface area

Feb 21, 2012

emc92

got stuck on doing the substitution.. any suggestions?

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Feb 21, 2012

SammyS

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emc92 said:

got stuck on doing the substitution.. any suggestions?

For one thing, the derivative of 1 + cos²(x) is -2sin(x)cos(x), not -2sin(x).

That substitution doesn't seem to help anyway.

Try u = cos(x) instead.

Feb 21, 2012

emc92

wow, i did not see that.
thanks so much!

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