What Is the Solution to This Logarithmic Problem?

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Kinda Tricky
 
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Not too tricky - it's just the Golden Ratio.
 
MajikWaffle said:
http://img228.imageshack.us/img228/1799/untitled8av.png
Kinda Tricky

A nice little question.

I'll give a hint.

9*16=144

12*12=144
 
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Yar, still can't get it. Answer anybody :smile:
 
The answer is in #2 above.
 
The problem is to find [itex]a/b[/itex] given
[tex]\log_9 a = \log_{12}b = \log_{16}(a+b)[/tex]

Let [tex]x = \log_9 a = \log_{12}b = \log_{16}(a+b)[/tex]. Then

[tex]a=9^x,~~~b=12^x,~~~a+b=16^x[/tex]

Now, compare [itex]a(a+b)[/itex] with [itex]b^2[/itex].
 
MajikWaffle said:
Yar, still can't get it. Answer anybody :smile:

We do not give out answers here at the PF. Show some effort, or your thread will be deleted.