[tex]\bf a^{u(x)}\qquad \qquad \cfrac{df}{dx}=\cfrac{df}{du}\cdot \cfrac{du}{dx}\\\\
-----------------------------\\\\
g(x)=3^{2x}\qquad \qquad u=2x
\\\\\\
\cfrac{dg}{dx}=3^uln(3)\cdot \cfrac{du}{dx}\implies \cfrac{dg}{dx}=3^{2x}ln(3)\cdot 2
\\\\\\
g'(2)=3^{2\cdot 2}ln(3)\cdot 2\implies g'(2)=2\cdot 81ln(3)\implies g'(2)=162ln(3)[/tex]