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Homework Help: Related rate problem

  1. Dec 23, 2003 #1
    What is the radius when the area in square units of an expanding circle is increasing twice as fast as the radius?
     
  2. jcsd
  3. Dec 23, 2003 #2

    Doc Al

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    Staff: Mentor

    Start with the area of a circle (A = πr2) and take the derivative with respect to time. Then apply what's given.
     
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