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Area of a circle

  1. Nov 7, 2003 #1
    Hello all. Where can I find proof that the area of a circle can be calculated using the formula πr2? Any response will be greatly appreciated, thank you.
  2. jcsd
  3. Nov 7, 2003 #2
    I believe it can be done using a limit process. Cut the circle into n equal triangles and take the limit as n goes to infinity.
  4. Nov 7, 2003 #3


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    Science Advisor

    And, of course, the area of a circle of radius R, with center at the origin of a coordinates system is the integral
    ∫-RR2√(R2- x2)dx. That gives πR2 as the area.
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