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Homework Help: BC Calculus - Related Rates

  1. Feb 1, 2009 #1
    1. The problem statement, all variables and given/known data

    When the area of an expanding square, in square units, is increasing three times as fast as its side is increasing, in linear units, the side is

    a.) 2/3
    b.) 3/2
    c) 3
    d) 2
    e) 1

    2. Relevant equations

    A = s^2
    dA/dt = 3s^2


    3. The attempt at a solution

    Can anyone give me hints on how to start this problem?
     
  2. jcsd
  3. Feb 1, 2009 #2

    Dick

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    Start by differentiating A=s^2 with respect to time correctly. Use implicit differentiation.
     
  4. Feb 1, 2009 #3
    Okay, Dick.

    I get dA/dt = 2s dS/Dt. Since it's saying that the area is increasing three times as fast as its side is increasing..... 2s must equal to 3. or s = 3/2

    is this correct?
     
  5. Feb 1, 2009 #4

    Dick

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    You betcha.
     
  6. Feb 1, 2009 #5
    Thank you, Sir.
     
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