easy peasy
just use PEMDAS and some exonential laws
\((x^{m})(x^{n})=x^{m+n}\)
\((x^{m})^{n}=x^{mn}\)
\((ab)^{m}=(a^{m})(b^{m})\)
also another is \(x^{\frac{m}{n}}=\sqrt[n]{x^{m}}\)
so
\([3(2a)^{\frac{3}{2}}]^{2}\)=
\((3^{2})((2a)^{\frac{3}{2}}^{2})\)=
\((9)((2a)^{\frac{3}{2}}^{2})\)=
\((9)((2a)^{\frac{6}{2})\)=
\((9)((2a)^{3})\) =
\((9)(8a^{3})\) =
\(72a^{3}\)
