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Homework Help: Indices (find X)

  1. Nov 28, 2004 #1

    Mo

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    Indices.Again i think i've got close to the answer, it just does not want to show its self! A push in the right direction would be appreciated ... heres the problem:

    [tex]2x^ \frac{1} {4} = \frac{64} {x} [/tex]

    Regards
    Mo
     
  2. jcsd
  3. Nov 28, 2004 #2
    Multiply both sides by x. Remember that x = x^1 and x^a * x^b = x^(a + b) for all a, b.
     
  4. Nov 28, 2004 #3

    Mo

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    Hmm i multiplied both sides by x ..i think the answer is:

    [tex]2x^ \frac{2} {4} = 64 [/tex] right?? ... carrying on ...

    then divide both sides by 2 ..so we are left with ..

    [tex]x ^\frac {2} {4} = 32 [/tex]

    am i along the right lines here??
     
  5. Nov 28, 2004 #4

    Hurkyl

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    Staff Emeritus
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    How did you get [itex]x^{2/4}[/itex]?
     
  6. Nov 28, 2004 #5

    Mo

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    hmm, i multiple both sides by x so

    [tex]2x^ \frac {1} {4} X x = 2x^ \frac {1} {4} X x^1[/tex]

    and since we add the indices when multiplying i get 2 no?
     
  7. Nov 28, 2004 #6

    Mo

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    oh lol i think i just spotted it ..
     
  8. Nov 28, 2004 #7

    Mo

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    edit: should be 1.25 right?

    Ack - stupid mistakes , i got it now.Completely overlooked it .. :blushing: .

    Thanks both :smile:
     
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