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Homework Help: Logs math help

  1. Apr 12, 2010 #1
    1. The problem statement, all variables and given/known data

    Simplify [tex](\log_a{b})(\log_b{c})(\log_c{d})[/tex] in terms of [tex]\log_x{y}[/tex]

    2. Relevant equations



    3. The attempt at a solution

    well , the furthest i can reach is

    [tex]\frac{\log_xd}{\log_xa}[/tex] , how do i express in terms of [tex]\log_x{y}[/tex]
     
  2. jcsd
  3. Apr 12, 2010 #2

    HallsofIvy

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    Science Advisor

    Re: logs

    Since there are no "x" or "y" in the problem I think you are misunderstanding.

    "in term so [itex]log_x y[/itex]" simply means "in terms of a single logarithm"

    You could, for example, put everything in terms of a logarithm base a:
    [tex]log_b c= \frac{log_a c}{log_a b}[/tex]
    and
    [tex]log_c d= \frac{log_a d}{log_a c}[/tex]
    so
    [tex](log_a b)(log_b c)(log_c d)= (log_a b)\frac{log_a c}{log_a b}\frac{log_a d}{log_a c}= log_a d[/tex]
     
  4. Apr 12, 2010 #3
    Re: logs

    thanks !
     
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