Ответ:

  1. а) \(\frac{1}{2}\sqrt{12}-2\sqrt{27}+\sqrt{75}=\sqrt{3}-6\sqrt{3}+5\sqrt{3}=0\).

    б) \(3\sqrt{2}(5\sqrt{2}-\sqrt{32})=3\sqrt{2}(5\sqrt{2}-4\sqrt{2})=3\sqrt{2}\cdot\sqrt{2}=6\).

    в) \((4-5\sqrt{2})^2=16-40\sqrt{2}+50=66-40\sqrt{2}\).

    г) \((\sqrt{7}-2\sqrt{3})(\sqrt{7}+2\sqrt{3})=7-12=-5\).

Ответ: а) 0; б) 6; в) \(66-40\sqrt{2}\); г) −5.