Theo mk là -3/21 lớn hơn -2/21
\(-\frac{2}{31};-\frac{3}{21}\)
=>\(-\frac{42}{651};-\frac{63}{651}\)
=>\(-\frac{42}{651}>-\frac{63}{651}=>-\frac{2}{31}>-\frac{3}{21}\)
\(-\frac{2}{31}\)và \(-\frac{3}{21}\)
Quy đồng:
\(-\frac{2}{31}=\frac{-2\times21}{31\times21}=\frac{-42}{651}\)
\(-\frac{3}{21}=\frac{-3\times31}{21\times31}=\frac{-93}{651}\)
Vì \(-42>-93\Rightarrow-\frac{2}{31}>\frac{-3}{21}\)
Mk ko chắc !
