\(\left(3\sqrt{12}-4\sqrt{3}+\sqrt{15}\right)\cdot\sqrt{3}-2\sqrt{5}\)
\(=\left(6\sqrt{3}-4\sqrt{3}+\sqrt{15}\right)\cdot\sqrt{3}-2\sqrt{5}\)
\(=6+3\sqrt{5}-2\sqrt{5}=6+\sqrt{5}\)
(3\(\sqrt{12}\)-4\(\sqrt{3}\)+\(\sqrt{15}\)).\(\sqrt{3}\)-2\(\sqrt{5}\)
=\(\left(6\sqrt{3}-4\sqrt{3}+\sqrt{15}\right).\sqrt{3}-2\sqrt{5}\)
=\(\left(2\sqrt{3}+\sqrt{15}\right).\sqrt{3}-2\sqrt{5}\)
=\(6+\sqrt{45}-2\sqrt{5}\)
=\(6+3\sqrt{5}-2\sqrt{5}\)
=\(6+\sqrt{5}\)