Question

(корень13+корень7)^2/10+корень91

Answer 1

$\dfrac{(\sqrt{13}+\sqrt{7})^2}{10+\sqrt{91}} = \dfrac{(\sqrt{13})^2+2\sqrt{13}\cdot \sqrt{7}+(\sqrt{7})^2}{10+\sqrt{91}} =\\ \\ \\=\dfrac{13+7+2\sqrt{91}}{10+\sqrt{91}} = \dfrac{2(10+\sqrt{91})}{10+\sqrt{91}} =2$