Answer
$81b^6$
Work Step by Step
We start with the given expression: $(9b^3)^2$
To raise a product to a power, we raise each factor to the power and multiply: $9^2(b^3)^2$
We simplify the constant power: $81(b^3)^2$
To raise a power to a power, we multiply the exponents: $81b^{3\times2}=81b^6$
