How Do You Calculate the Area Bounded by a Polar Curve?

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will_lansing
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[SOLVED] Area of Polar Coordinates

Homework Statement


Find the area of the region bounded by r=6-4sin[tex]\Theta[/tex]


Homework Equations


A=(1/2)[tex]\int[/tex] r[tex]^{2}[/tex] d[tex]\Theta[/tex]


The Attempt at a Solution


I'm not sure what the bounds are but I thought they were 0 to 2pi. Am I wrong if so how then do you go about finding the bounds?
A=(1/2)[tex]\int[/tex] [36-48sin[tex]\Theta[/tex]+16sin^2[tex]\Theta[/tex] d[tex]\Theta[/tex]
A=(1/2)[36[tex]\Theta[/tex]-48cos[tex]\Theta[/tex]+8[tex]\Theta[/tex]-4sin2[tex]\Theta[/tex]]

and i got the answer to be 63.5 where did i go wrong?
 
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How do get [tex]44\pi=63.5[/tex]?
 
I'm not sure what i did. I think i typed in the wrong thing in my calculator or something. but i just plugged 2pi and 0 in for theta, but i still got the wrong answer. What am i suppose to do.
 
Do it by hand, then, and see if you get 44*pi.

One possible reason why your calc gave you something else than that might be that your calculator is measuring angles in degrees instead of radians.
 
yeah you're right i forgot to change back to radians, i feel so stupid now. well thanks, maybe i should just do by hand and not put so much trust in the calculator.