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Find x

  1. Sep 22, 2008 #1
    how can u solve this equation (3^x)-(3^-x)=4...hehe:P
    please i really need it fast..TT
    Last edited: Sep 22, 2008
  2. jcsd
  3. Sep 22, 2008 #2


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    "please i really need it fast."

    That's not how it works - you need to show some of your first tries, or explain what you've done that hasn't worked. At that time you may receive hints.
  4. Sep 22, 2008 #3
    Hmm.. to get you started, multiply everything by 3^(x).. from there everything is bright and clear.
  5. Sep 23, 2008 #4
    then take a substitution of the form [tex] t=3^x[/tex] so u'll get a quadratic eq.
  6. Sep 23, 2008 #5


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    once you get you solve the quadratic, don't forget to substitute 3x=t back again :smile:
  7. Sep 23, 2008 #6
    Guys we've helped enough now let the OP do the math.
  8. Sep 24, 2008 #7
    damn!!you people are damn good!:P i tried many times but nothing happens..THX GUYS:)
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