a) \(\frac{{ - 21}}{{10}}\) < 0
b) \(\frac{{ - 5}}{{ - 2}} = \frac{5}{2} > 0\). Vậy \(\frac{{ - 5}}{{ - 2}} > 0\).
c) \(\frac{{ - 5}}{{ - 2}} = \frac{5}{2} > 0\), mà \(\frac{{ - 21}}{{10}} < 0\)
Vậy \(\frac{{ - 5}}{{ - 2}} > \frac{{ - 21}}{{10}}\).
a: \(-\dfrac{21}{10}< 0\)
b: \(0< -\dfrac{5}{-2}\)
c: \(-\dfrac{21}{10}< 0< \dfrac{-5}{-2}\)