2730.33 – Love Those Logarithms


Find log26(323)\log_{\sqrt[6]{2}}{\left( \sqrt[3]{32} \right)}. Note the unusual base of this logarithm.


Solution

Let x=log26(323)x = \log_{\sqrt[6]{2}}{\left( \sqrt[3]{32} \right)}. What this means is that

(26)x=323.\left( \sqrt[6]{2} \right)^x = \sqrt[3]{32}.

By manipulation of both sides of this equality, one can discover xx in a simpler form. Thus,

(26)x=3232(16)x=2532(x6)=2(53)\begin{aligned}\left( \sqrt[6]{2} \right)^x &= \sqrt[3]{32} \\2^{\left( \dfrac{1}{6} \right) ^ x} &= \sqrt[3]{2^5} \\2^{ \left( \dfrac{x}{6} \right)} &= 2^{\left(\dfrac{5}{3}\right)}\end{aligned}

Therefore x6=53\dfrac{x}{6} = \dfrac{5}{3} from which follows x=10x = 10.

Were we expecting such a simple answer for such a messy-looking problem?