3. Сократите дробь: a) 5-√5 10-√2;

Сократим дробь $$\frac{5-\sqrt{5}}{\sqrt{10}-\sqrt{2}}$$.

1. $$\frac{5-\sqrt{5}}{\sqrt{10}-\sqrt{2}} = \frac{\sqrt{5}(\sqrt{5}-1)}{\sqrt{2}(\sqrt{5}-1)} = \frac{\sqrt{5}}{\sqrt{2}} = \frac{\sqrt{5}\cdot \sqrt{2}}{\sqrt{2}\cdot \sqrt{2}} = \frac{\sqrt{10}}{2}$$

Ответ: $$\frac{\sqrt{10}}{2}$$