Question

giúp con b

Answer 1

\(b,\dfrac{2}{14}+\dfrac{-2}{11}+\dfrac{6}{7}+\dfrac{9}{-11}+\dfrac{1}{12}\\ =\left(\dfrac{2}{14}+\dfrac{6}{7}\right)\left(\dfrac{-2}{11}+\dfrac{-9}{11}\right)+\dfrac{11}{12}\\ =\left(\dfrac{2}{14}+\dfrac{12}{14}\right)+\dfrac{-11}{11}+\dfrac{11}{12}\\ =1+\left(-1\right)+\dfrac{11}{12}\\ =\dfrac{11}{12}\)