Question

[Sách Giáo Khoa]

Đưa thừa số vào trong dấu căn:

\(3\sqrt{5};-5\sqrt{2};-\dfrac{2}{3}\sqrt{xy}\) với \(xy\ge0;x\sqrt{\dfrac{2}{x}}\) với x > 0.

Answer 1

[¨°o.O♫♀¤♪ Zin Phan ♪¤♂♫O.o°¨]

3\(\sqrt{5}\)= \(\sqrt{3^2.5}\)=\(\sqrt{45}\)

-5\(\sqrt{2}\)= \(-\sqrt{5^2.2}\)= -\(\sqrt{50}\)

\(\dfrac{-2}{3}\sqrt{xy}\) = \(-\sqrt{\left(\dfrac{2}{3}\right)^2xy}\) = -\(\sqrt{\dfrac{4}{9}xy}\)

x\(\sqrt{\dfrac{2}{x}}\)= \(\sqrt{\dfrac{2x^2}{x}}=\sqrt{2x}\)

Answer 2

[Ho Truc]

\(3\sqrt{5}=\sqrt{45}\)