188. Вычислить: а) \(\frac{4\sqrt{40}}{\sqrt{10}}\); б) \(\frac{20\sqrt{18}}{5\sqrt{2}}\); в) \(\frac{\sqrt{98}}{2\sqrt{2}}\); г) \(\frac{\sqrt{200}}{5\sqrt{8}}\).

1. \(\displaystyle \frac{4\sqrt{40}}{\sqrt{10}}=4\sqrt{\frac{40}{10}}=4\sqrt4=8\).
2. \(\displaystyle \frac{20\sqrt{18}}{5\sqrt2}=4\sqrt{\frac{18}{2}}=4\sqrt9=12\).
3. \(\displaystyle \frac{\sqrt{98}}{2\sqrt2}=\frac{\sqrt{98}}{\sqrt8}=\sqrt{\frac{98}{8}}=\sqrt{\frac{49}{4}}=\frac72\).
4. \(\displaystyle \frac{\sqrt{200}}{5\sqrt8}=\frac{\sqrt{200}}{\sqrt{200}}=1\).

Ответ: а) 8; б) 12; в) \(\frac72\); г) 1.