WordGPT

Which is bigger, 2172^{17} or 17217^{2}?

2172^{17} is bigger: 2172^{17} = 131072 and 17217^{2} = 289.

The curve ln x / x, which decides every comparison of a^b with b^a2468101214161820-0.10.10.20.30.4x = 2x = 17peak at eln x / x
The curve ln x / x, which decides every comparison of a^b with b^a. 2^17 against 17^2 is the same question as which of the two marked points is higher; the curve peaks at x = e.

How to work it out

  1. 1

    Compute both exactly: 2172^{17} = 131072 and 17217^{2} = 289.

  2. 2

    So 2172^{17} is bigger.

  3. 3

    The reason: taking logs, aba^{b} against bab^{a} is the same as ln⁡aa\frac{\ln a}{a} against ln⁡bb\frac{\ln b}{b}. The function ln⁡xx\frac{\ln x}{x} rises until x=e≈2.718x = e \approx 2.718 and falls afterwards. For 2 and 17 it depends: 242^{4} = 424^{2} are equal, 232^{3} < 323^{2}, and 2b2^{b} > b2b^{2} for every b ≥ 5.

    ln⁡22 > ln⁡1717\frac{\ln 2}{2}\ >\ \frac{\ln 17}{17}
LaTeX source of the formulas on this page
\[ 2^{17} = 131072\ >\ 17^{2} = 289 \]
\[ \frac{\ln 2}{2}\ >\ \frac{\ln 17}{17} \]

Questions

Which is bigger, 2172^{17} or 17217^{2}?

2172^{17} is bigger: 2172^{17} = 131072 and 17217^{2} = 289.

Similar comparisons

    Which is bigger, 2^17 or 17^2? 2^17 | WordGPT