Question 536039
<pre>  
{{{2^a}}} = 3

Cube both sides:

{{{(2^a)^3}}} = {{{3^3}}}

Use the rule of exponents {{{(X^Y)^Z}}} = {{{X^(YZ)}}} and replace 3³ by 27

{{{2^(3a)}}} = 27

Use that same rule of exponents in reverse: {{{X^(YZ)}}} = {{{(X^Y)^Z}}}
 
{{{(2^3)^a}}} = 27

Replace 2³ by 8

{{{8^a}}} = 27

Edwin</pre>