Find any critical numbers of: f(theta) = 2sec(theta) + tan(theta), 0<theta<2pi.

I found the defivative, but I got stuck.

I got to 2tan(theta)=-sin(theta).

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- October 31st 2007, 10:57 PMunluckykcFind Critical numbers
Find any critical numbers of: f(theta) = 2sec(theta) + tan(theta), 0<theta<2pi.

I found the defivative, but I got stuck.

I got to 2tan(theta)=-sin(theta). - October 31st 2007, 10:59 PMJhevon
- October 31st 2007, 11:08 PMunluckykc
Oh, sorry. I got to include the steps.

f'(theta) = 2sec(theta)tan(theta) + sec^2(theta)

I set it equal to zero, factored out a sec(theta). I was left with 2 equations: sec(theta)=0 and 2tan(theta) + sec(theta) = 0 =>2tan(theta) = -sec(theta) {I didn't mean sin before...I meant sec} - October 31st 2007, 11:14 PMJhevon