Which is bigger, or ?
is bigger: = 1953125 and = 59049.
How to work it out
- 1
Compute both exactly: = 1953125 and = 59049.
- 2
So is bigger.
- 3
The reason: taking logs, against is the same as against . The function rises until and falls afterwards. Both 5 and 9 are past e, where the function is decreasing, so the larger exponent loses and > .
LaTeX source of the formulas on this page
\[ 5^{9} = 1953125\ >\ 9^{5} = 59049 \]
\[ \frac{\ln 5}{5}\ >\ \frac{\ln 9}{9} \]Questions
Which is bigger, or ?
is bigger: = 1953125 and = 59049.