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Homework Help: Solve for x

  1. Dec 7, 2004 #1
    2^x=7*5^x
    I know you have to take ln of both sides but i am having trouble doing that for the right side.
     
  2. jcsd
  3. Dec 7, 2004 #2

    shmoe

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    Remember the property of logarithms, ln(ab)=ln(a)+ln(b). That should help you deal with the right hand side.
     
    Last edited: Dec 7, 2004
  4. Dec 7, 2004 #3

    dextercioby

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    I could give u the only hint possible,but that would be useless.So i'll better show u my version.Logarithmate both sides of the equation to find:
    [tex] x\ln 2=\ln 7+x\ln 5 =>x=\frac{\ln 7}{\ln 2-\ln 5} [/tex].

    Okay...??Clear???

    PS:Shmoe,u were quicker than me...Again. :tongue2:
     
  5. Dec 7, 2004 #4
    Yeah thanks alot i was messing up and having ln7*xln5
     
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