Question 946386
Really unclear what expression you have.
GUESS:  {{{((7y)^12)^7}}}.


Here is a rule to understand:'
{{{(B^(r))^s=B^(rs)}}}.



Your expression may be then,
{{{(7y)^(12*7)}}}
{{{7y^(84)}}}
{{{highlight(7^84*y^84)}}}.