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What am i doing wrong

  1. Jun 7, 2010 #1

    I am trying to simplify this equation and it won't work using this method, although i can do it using another method, so this method should work too. Could someone please look at my working and tell me where im going wrong?

    2A^-(1/2)=t^-1 +1
    A^(-1/2)=(t^-1 +1)/2
    A^(1/2)=2/(t^-1 +1)
    A=(2/(t^-1 +1))^(1/2)

    Surely this should work, but the answer which is correct and i can get using another method is A=(4t^2)/(1+t)^2

    Thanks for your help
  2. jcsd
  3. Jun 7, 2010 #2


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    Homework Helper

    This step is incorrect. The right hand side of the last line should be raised to the power of 2, not 1/2. Once this error is fixed to get the "correct" form, just multiply top and bottom by t^2. (Or in the first line in the quote above, multiply by t on top and bottom, and then square both sides).
  4. Jun 7, 2010 #3
    Thanks so much, i thought it must be something stupid..
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