Question

9 задание
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Answer 1

$\frac{2\sqrt5-5\sqrt2-\sqrt{10}}{\sqrt{10}+\sqrt2-2}=\frac{\sqrt{20}-\sqrt{50}-\sqrt{10}}{\sqrt{10}+\sqrt2-\sqrt4}=\frac{\sqrt{10}(\sqrt2-\sqrt5-1)}{\sqrt2(\sqrt5+1-\sqrt2)}=-\frac{\sqrt{10}}{\sqrt2}=-\sqrt5$