Question

so sánh hai phân số

\(\frac{19}{23}\)và \(\frac{1919}{2323}\)

\(\frac{101010}{606060}\)và \(\frac{10}{60}\)

\(\frac{122}{123}\)và \(\frac{123123}{124124}\)

Answer 1

a) Ta có :

\(\frac{19}{23}=\frac{19.101}{23.101}=\frac{1919}{2323}\)

\(\Rightarrow\frac{19}{23}=\frac{1919}{2323}\)

b) Ta có 

\(\frac{10}{60}=\frac{10.10101}{60.10101}=\frac{101010}{606060}\)

\(\Rightarrow\frac{10}{60}=\frac{101010}{606060}\)

c) Ta có 

\(\frac{123}{124}=\frac{123.1001}{124.1001}=\frac{123123}{124124}\)

\(\Rightarrow\frac{123}{124}=\frac{123123}{124124}\)

Xét :

\(\frac{122}{123}-1=-\frac{1}{123}\)

\(\frac{123}{124}-1=-\frac{1}{124}\)

Vì \(-\frac{1}{123}< -\frac{1}{124}\)

\(\Rightarrow\frac{122}{123}< \frac{123}{124}\)

\(\Rightarrow\frac{122}{123}< \frac{123123}{124124}\)