Question

Answer 1

2) Ta có: \(\dfrac{14}{21}=\dfrac{2}{3}=\dfrac{4}{6}\)

\(\dfrac{60}{72}=\dfrac{5}{6}\)

mà \(\dfrac{4}{6}< \dfrac{5}{6}\)

nên 1\(\dfrac{14}{21}< \dfrac{60}{72}\)

Answer 2

1)

a)(-6-3).(-6+3)=(-9).(-3)                             b)(-34).46+66.(-46)=46.(-34-66)

                     =27                                                                   =46(-100)=-4600

                                                c)\(\dfrac{5}{13}+\dfrac{-5}{7}+\dfrac{-20}{41}+\dfrac{8}{13}+\dfrac{21}{-41}=\left(\dfrac{5}{13}+\dfrac{8}{13}\right)+\left(-\dfrac{20}{41}-\dfrac{21}{41}\right)+\left(-\dfrac{5}{7}\right)\)                                                  \(1+\left(-1\right)+\left(-\dfrac{5}{7}\right)=\dfrac{-5}{7}\)

2)

\(\dfrac{14}{21}=\dfrac{2}{3}=\dfrac{4}{6}\)

\(\dfrac{60}{72}=\dfrac{5}{6}\)

=>\(\dfrac{4}{6}< \dfrac{5}{6}=>\dfrac{14}{21}< \dfrac{60}{72}\)

Chúc bn học tốt