Question

cho tớ hỏi 15 căn 1/5 thì tách như nào vậy ạ??

Answer 1

\(15\sqrt{\dfrac{1}{5}}=\dfrac{15}{\sqrt{5}}=3\sqrt{5}\)

Answer 2

\(15\sqrt{\dfrac{1}{5}}\)

\(=\sqrt{15^2\cdot\dfrac{1}{5}}\)

\(=\sqrt{\dfrac{225}{5}}\)

\(=\sqrt{45}\)

\(=\sqrt{3^2\cdot5}\)

\(=3\sqrt{5}\)