Question

Answer 1

\(A=\dfrac{2\left(\dfrac{1}{3}+\dfrac{1}{5}-\dfrac{1}{9}\right)}{4\left(\dfrac{1}{3}+\dfrac{1}{5}-\dfrac{1}{9}\right)}=\dfrac{2}{4}=\dfrac{1}{2}\)

Answer 2

\(A =\dfrac{ \dfrac{2}{3} + \dfrac{2}{5} - \dfrac{2}{9} }{ \dfrac{4}{3} + \dfrac{4}{5} - \dfrac{4}{9}}\)

\(A = \dfrac{ 1 . ( \dfrac{2}{3} + \dfrac{2}{5} - \dfrac{2}{9})}{2 . ( \dfrac{2}{3} + \dfrac{2}{5} - \dfrac{2}{9})}\)

\(A = \dfrac{1}{2}\)

\(\text{ Vậy } \) \(A = \dfrac{1}{2}\)