Giá trị của biểu thức \(C=\dfrac{\dfrac{5}{22}+\dfrac{3}{13}-\dfrac{1}{2}}{\dfrac{4}{13}-\dfrac{2}{11}+\dfrac{3}{2}}\) là
\(-\dfrac{4}{155}\). \(\dfrac{4}{155}\). \(-\dfrac{1}{31}\). \(\dfrac{1}{31}\). Hướng dẫn giải:\(C=\dfrac{\dfrac{5}{22}+\dfrac{3}{13}-\dfrac{1}{2}}{\dfrac{4}{13}-\dfrac{2}{11}+\dfrac{3}{2}}\)
\(=\dfrac{\left(\dfrac{5}{22}+\dfrac{3}{13}-\dfrac{1}{2}\right).\left(2.11.13\right)}{\left(\dfrac{4}{13}-\dfrac{2}{11}+\dfrac{3}{2}\right)\left(2.11.13\right)}\)
\(=\dfrac{65+66-143}{88-52+429}=\dfrac{-4}{155}\).
