Question

10-2√7/(-3)-√7 в виде d+e√7

Answer 1

$\frac{10-2\sqrt{7}}{-3-\sqrt{7}} = \frac{(10-2\sqrt{7})(-3+\sqrt{7})}{(-3-\sqrt{7})(-3+\sqrt{7})} = \frac{(10-2\sqrt{7})(-3+\sqrt{7})}{-(3+\sqrt{7})(-3+\sqrt{7})} = \frac{-30+6\sqrt{7}+10\sqrt{7}-2\sqrt{7}\sqrt{7}}{-(7-9)} =\frac{16\sqrt{7}-30-14}{-(-2)} = \frac{16\sqrt{7}-44}{2} = 8\sqrt{7} -22$