a) Ta có: \(\left(\sqrt{12}+2\sqrt{27}\right)\cdot\dfrac{\sqrt{3}}{2}-\sqrt{150}\)
\(=8\sqrt{3}\cdot\dfrac{\sqrt{3}}{2}-5\sqrt{6}\)
\(=12-5\sqrt{6}\)
b) Ta có: \(\left(\sqrt{28}-\sqrt{12}-\sqrt{7}\right)+2\sqrt{21}\)
\(=\sqrt{7}-2\sqrt{3}+2\sqrt{21}\)