\(B)\dfrac{123}{-124}\) và \(\dfrac{-310}{311}\)

Ta có: \(1-\dfrac{123}{124}=\dfrac{1}{124}\)\(;1-\dfrac{310}{311}=\dfrac{1}{311}\)

Có: \(\dfrac{1}{124}>\dfrac{1}{311}\Leftrightarrow1-\dfrac{123}{124}>1-\dfrac{310}{311}\)\(\Leftrightarrow1+\left(-\dfrac{123}{124}\right)>1+\left(-\dfrac{310}{311}\right)\Leftrightarrow-\dfrac{123}{124}>-\dfrac{310}{311}\)

Hay \(\dfrac{123}{-124}>\dfrac{-310}{311}\)

Vậy \(\dfrac{123}{-124}>\dfrac{-310}{311}\)

So sánh các phân số

a)\(\dfrac{12}{14};\dfrac{1212}{1414};\dfrac{121212}{141414}\)

b)\(\dfrac{24}{35};\dfrac{2424}{3535};\dfrac{242424}{353535}\)

c)\(\dfrac{22}{25}\) và \(\dfrac{224466}{255075}\)

d)\(\dfrac{122436}{132639}\)và \(\dfrac{12}{13}\)

\(a,\dfrac{1212}{1414}=\dfrac{1212\div101}{1414\div101}=\dfrac{12}{14};\dfrac{121212}{141414}=\dfrac{121212\div10101}{141414\div10101}=\dfrac{12}{14}\)

Vì \(\dfrac{12}{14}=\dfrac{12}{14}=\dfrac{12}{14}\)nên ...

\(b,\dfrac{2424}{3535}=\dfrac{2424\div101}{3535\div101}=\dfrac{24}{35};\dfrac{242424}{353535}=\dfrac{242424\div10101}{353535\div10101}=\dfrac{24}{35}\)

Vì \(\dfrac{24}{35}=\dfrac{24}{35}=\dfrac{24}{35}\)nên ...

Mình làm cho bạn 2 phần đầu này thôi nhé , phần sau bạn làm tiếp nhé !