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Help finding x

  1. Nov 15, 2003 #1
    Hi, I am having trouble finding x for the following exquation:
    2x=16-3/4 * sqrt(2)

    Any help on solving it would be much apprecitated.
     
    Last edited: Nov 15, 2003
  2. jcsd
  3. Nov 15, 2003 #2

    dduardo

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    why don't you use logs.

    2^x = 16^(-3/4) * sqrt(2)

    x*ln(2) = ln(16^(-3/4) * sqrt(2) )

    x = ln(16^(-3/4) * sqrt(2) ) / ln(2)
     
  4. Nov 15, 2003 #3

    jcsd

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    reduce it further to:

    x = -2.5
     
  5. Nov 15, 2003 #4

    dduardo

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    jcsd, your i see you changed your reduction. The previous one was obviously wrong.
     
  6. Nov 15, 2003 #5
    Is it possible to find x not using logs?
     
  7. Nov 15, 2003 #6

    jcsd

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    Duardo: No, it was perfectly correct.
     
  8. Nov 15, 2003 #7

    dduardo

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    yes.

    you can convert 16 to a base 2

    16^(-3/4) = (2^4)^(-3/4) = 2^(-3)

    therefore

    2^x = 2^(-3) * 2^(1/2)

    2^x = 2^(-5/2)

    x = -2.5
     
  9. Nov 16, 2003 #8
    This is probably off topic, but don't you just love logs?
     
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