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Finding the area enclosed by r=3sin theta 
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#1
Dec1508, 01:43 PM

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1. The problem statement, all variables and given/known data
Find the area enclosed inside r=3 sin (theta) 2. Relevant equations integral? 3. The attempt at a solution basically, I took [tex]\int3sin\Theta[/tex] from 0 to 2pi, then pulled the 3 out to get [tex]3\int sin\Theta[/tex] from 0 to 2pi and then [tex]3[cos(\Theta)][/tex] evaluated from 0 to 2pi. that seems too easy. what am I missing? 


#2
Dec1508, 01:58 PM

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Who said everything has to be super hard? But if you work that out, you'll get 0 for the area. Is that right? It might help to draw a picture. And, hey, area in polar coordinates isn't the integral of r dtheta, is it? Would you look up the right formula for area?



#3
Dec1508, 04:00 PM

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ah. that's what it was. I forgot about the formula for area. : (
Thanks! 


#4
Dec1508, 04:55 PM

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Finding the area enclosed by r=3sin theta



#5
Dec1508, 05:00 PM

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#6
Dec1508, 10:15 PM

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The integral of r*dtheta*dr is the area. Not the integral of r*dtheta. I missed it at my first reading as well.



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