Cho các biểu thức \(A=1-\dfrac{1}{6};B=\dfrac{1}{2}-\dfrac{1}{3};C=\dfrac{1}{5}-\dfrac{1}{7}\). Tính A + B + C.
\(\dfrac{7}{35}.\)\(\dfrac{35}{37}.\)\(\dfrac{37}{35}.\)\(\dfrac{5}{37}.\)Hướng dẫn giải:\(A+B+C =1-\dfrac{1}{6}+\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{5}-\dfrac{1}{7}\)
\(=1-\Big(\dfrac{1}{6}-\dfrac{1}{2}+\dfrac{1}{3}\Big)+\Big(\dfrac{1}{5}-\dfrac{1}{7}\Big)\)
\(=1-0+\dfrac{2}{35}\)
\(=1+\dfrac{2}{35}=\dfrac{37}{35}.\)
