`2/7=[2xx3]/[7xx3]=6/21`
`1/3=[1xx7]/[3xx7]=7/21`
Vì `6 < 7` nên `2/7 < 1/3`
`2/7=(2xx3)/(7xx3)=6/21`
`1/3=(1xx7)/(3xx7)=7/21`
Vì : `6/21<7/21`
Nên : `2/7<1/3`
Ta có: \(\dfrac{2}{7}=\dfrac{6}{21};\dfrac{1}{3}=\dfrac{7}{21}\)
Vì: \(\dfrac{6}{21}< \dfrac{7}{21}\) nên \(\dfrac{2}{7}< \dfrac{1}{3}\)
Ta sẽ chọn dấu < nhé!