Question

A 7ab. \(\sqrt{\dfrac{36a^4}{49b^2}}\) với b > 0

Answer 1

\(7ab\cdot\sqrt{\dfrac{36a^4}{49b^2}}\\ =>7ab\cdot\sqrt{\left(\dfrac{6a^2}{7b}\right)^2}\\ =>7ab\cdot\dfrac{6a^2}{7b}\\ =>\dfrac{7ab\cdot6a^2}{7b}\\ =>6a^3\)

Answer 2

\(A=7ab.\sqrt{\dfrac{36a^4}{49b^2}}\)

\(=7ab.\dfrac{6a^2}{\left|7b\right|}\)

\(=7ab.\dfrac{6a^2}{7b}\left(vib>0\right)\)

\(=6a^3\)