Question 1067390
{{{ 25^log5(4) }}} = 

{{{ (5^2)^log5(4) }}} =
{{{  5^log5(4^2) }}} =
{{{   5^log5(16) }}} = 
{{{ highlight(16) }}}
 
( by definition of log_n(x): {{{ n^log_n(k) = k }}}