Which is Greater: $\log_9 25$ or $\log_4 9$?

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SUMMARY

The discussion centers on comparing the logarithmic values of $\log_9 25$ and $\log_4 9$. Through analysis, it is established that $\log_4 9$ is greater than $\log_9 25$. The calculations involve converting both logarithms to a common base, revealing that $\log_4 9$ approximates to 1.5 while $\log_9 25 approximates to 2/3. This definitive conclusion is supported by mathematical properties of logarithms.

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Which of the following two is greater?

$\log_9 25$ and $\log_4 9$
 
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anemone said:
Which of the following two is greater?

$\log_9 25$ and $\log_4 9$

$9^{1.5} = 3^3 = 27$
$4^{1.5} = 2^3 = 8$

so $\log_9 27$ = $\log_4 8$
or $\log_9 25$ < $\log_9 27$ = $\log_4 8$ < $\log_4 9$

hence $\log_4 9$ is greater
 
Very good, kaliprasad and thanks for participating!

My solution:

$\log_9 25<\log_9 26<\dfrac{\log_4 26}{\log_4 9}<\dfrac{\log_4 26}{\log_4 8}=\dfrac{\log_4 (26)^2}{3}=\dfrac{\log_4 676}{3}<\dfrac{\log_4 729}{3}=\log_4 9$
 
anemone said:
Very good, kaliprasad and thanks for participating!

My solution:

$\log_9 25<\log_9 26<\dfrac{\log_4 26}{\log_4 9}<\dfrac{\log_4 26}{\log_4 8}=\dfrac{\log_4 (26)^2}{3}=\dfrac{\log_4 676}{3}<\dfrac{\log_4 729}{3}=\log_4 9$

it should be $\log_9 26=\dfrac{\log_4 26}{\log_4 9}$ (a typo)
 

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