Question 703686
The rules of indices says that if you have a number raised to a power in a bracket and a power outside the bracket, the number stays the same and you multiply the indices.
Eg,
{{{(4x^3)^5}}} = {{{4x^15}}}
we just multiply the power 3 inside the bracket and the power 5 outside the bracket
So in your problem {{{(3x^(2y))^3}}} we multiply the power 2y and the power 3 together
3 times 2y = 6y
giving
{{{3x^(6y)}}}