Question

Помогите пжпжпжпжпжпж​

Answer 1

$\displaystyle\tt \frac{6}{1-\sqrt{7}} -\frac{2}{\sqrt{7}+3}=\frac{6(1+\sqrt{7})}{(1-\sqrt{7})(1+\sqrt{7})} -\frac{2(\sqrt{7}-3)}{(\sqrt{7}+3)(\sqrt{7}-3)}=\\\\\\=\frac{6(1+\sqrt{7})}{1-7} -\frac{2(\sqrt{7}-3)}{7-9}=\frac{6(1+\sqrt{7})}{-6} -\frac{2(\sqrt{7}-3)}{-2}=\\\\\\=-(1+\sqrt{7})+\sqrt{7}-3=-1-\sqrt{7}+\sqrt{7}-3=-4$