Question

Помогите, пожалуйста решить!

Answer 1

$\displaystyle \tt \bigg(\sqrt{8+\sqrt{15}}+\sqrt{8-\sqrt{15}}\bigg)^{2}=\\\\\\=\bigg(\sqrt{8+\sqrt{15}}\bigg)^{2}+2\cdot\sqrt{8+\sqrt{15}}\cdot\sqrt{8-\sqrt{15}}+\bigg(\sqrt{8-\sqrt{15}}\bigg)^{2}=\\\\\\=8+\sqrt{15}+2\cdot\sqrt{(8+\sqrt{15})(8-\sqrt{15})}+8-\sqrt{15}=\\\\\\=16+2\cdot\sqrt{64-15}=16+2\cdot7=30;$