Question

Tính:

\(\sqrt{\dfrac{1}{9}.}\sqrt{0,8+\sqrt{ }0,09}\)                ,      \(\left(\dfrac{2}{5}\sqrt{16+2}\sqrt{\dfrac{16}{25}}\right):2\sqrt{\dfrac{1}{16}}\)

Answer 1

a: Sửa đề: \(\sqrt{\dfrac{1}{9}}\cdot\sqrt{0.8}+\sqrt{0.09}\)

\(=\dfrac{1}{3}\cdot\dfrac{2}{\sqrt{5}}+\dfrac{3}{10}=\dfrac{2\sqrt{5}}{15}+\dfrac{3}{10}=\dfrac{4\sqrt{5}+9}{30}\)

b: Sửa đề: \(\left(\dfrac{2}{5}\sqrt{16}+2\sqrt{\dfrac{16}{25}}\right):2\sqrt{\dfrac{1}{16}}\)

\(=\left(\dfrac{2}{5}\cdot4+2\cdot\dfrac{4}{5}\right):\left(2+\dfrac{1}{4}\right)\)

\(=\dfrac{16}{5}:\dfrac{9}{4}=\dfrac{16}{5}\cdot\dfrac{4}{9}=\dfrac{64}{45}\)