Question

Answer 1

\(\dfrac{\dfrac{2}{5}+\dfrac{2}{7}-\dfrac{2}{9}-\dfrac{2}{11}+\dfrac{2}{13}}{\dfrac{3}{5}+\dfrac{3}{7}-\dfrac{3}{9}-\dfrac{3}{11}+\dfrac{3}{13}}+\dfrac{15151515}{45454545}\\ =\dfrac{2\left(\dfrac{1}{5}+\dfrac{1}{7}-\dfrac{1}{9}-\dfrac{1}{11}+\dfrac{1}{13}\right)}{3\left(\dfrac{1}{5}+\dfrac{1}{7}-\dfrac{1}{9}-\dfrac{1}{11}+\dfrac{1}{13}\right)}+\dfrac{1}{3}\\ =\dfrac{2}{3}+\dfrac{1}{3}\\ =\dfrac{3}{3}\\ =1\)

Chọn A