Question

срочно, алгебра
подробно расписать

Answer 1

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