\(A=\dfrac{2\sqrt{3}}{\sqrt{3}+1}+3\sqrt{\dfrac{1}{6}}\cdot\sqrt{\dfrac{1}{2}}-\sqrt{12}\)
\(A=\dfrac{2\sqrt{3}\left(\sqrt{3}-1\right)}{\left(\sqrt{3}-1\right)\left(\sqrt{3}+1\right)}+3\cdot\dfrac{1}{\sqrt{6}}\cdot\dfrac{1}{\sqrt{2}}-2\sqrt{3}\)
\(A=\dfrac{2\sqrt{3}\cdot\left(\sqrt{3}-1\right)}{2}+3\cdot\dfrac{1}{\sqrt{12}}-2\sqrt{3}\)
\(A=\sqrt{3}\cdot\left(\sqrt{3}-1\right)+3\cdot\dfrac{1}{2\sqrt{3}}-2\sqrt{3}\)
\(A=3-\sqrt{3}+\dfrac{3}{2\sqrt{3}}-2\sqrt{3}\)
\(A=3-3\sqrt{3}+\dfrac{\sqrt{3}}{2}\)
\(A=\dfrac{6+6\sqrt{3}+\sqrt{3}}{2}\)
\(A=\dfrac{6+7\sqrt{3}}{2}\)