d)\(\dfrac{3}{14}=\dfrac{3\times4}{14\times4}=\dfrac{12}{56};\dfrac{4}{15}=\dfrac{4\times3}{15\times3}=\dfrac{12}{45};\dfrac{6}{17}=\dfrac{6\times2}{17\times2}=\dfrac{12}{34}\)
Vì \(56>45>34=>\dfrac{12}{56}< \dfrac{12}{45}< \dfrac{12}{34}=>\dfrac{3}{14}< \dfrac{4}{15}< \dfrac{6}{17}\)
e)\(\dfrac{13}{-36}=\dfrac{-13}{36};-\dfrac{7}{18}=\dfrac{-7\times2}{18\times2}=\dfrac{-14}{36};\dfrac{-5}{12}=\dfrac{-5\times3}{12\times3}=\dfrac{-15}{36}\)
Vì \(\dfrac{-13}{36}>\dfrac{-14}{36}>\dfrac{-15}{36}=>\dfrac{13}{-36}>-\dfrac{7}{18}>\dfrac{-5}{12}\)
g)\(\dfrac{-12}{17}=\dfrac{-12\times4}{17\times4}=\dfrac{-48}{68};\dfrac{-8}{15}=\dfrac{-8\times6}{15\times6}=\dfrac{-48}{90};\dfrac{16}{-2}=\dfrac{16\times3}{-2\times3}=\dfrac{-48}{6}\)
Vì \(90>68>6=>\dfrac{48}{90}>\dfrac{48}{68}>\dfrac{48}{6}=>\dfrac{-48}{90}< \dfrac{-48}{68}< \dfrac{-48}{6}=>\dfrac{-8}{15}< \dfrac{-12}{17}< \dfrac{16}{-2}\)
a)\(\dfrac{13}{21}=\dfrac{13\times2}{21\times2}=\dfrac{26}{42};\dfrac{9}{14}=\dfrac{9\times3}{14\times3}=\dfrac{27}{42}\)
Ta có:\(\dfrac{26}{42}< \dfrac{27}{42}=>\dfrac{13}{21}< \dfrac{9}{14}\)
b)\(\dfrac{6}{17}=\dfrac{6\times9}{17\times9}=\dfrac{54}{153};\dfrac{9}{25}=\dfrac{9\times6}{25\times6}=\dfrac{54}{150}\)
Vì \(153>150=>\dfrac{54}{153}< \dfrac{54}{150}=>\dfrac{6}{17}< \dfrac{9}{25}\)
c)\(\dfrac{7}{-12}=\dfrac{-7}{12}=\dfrac{-7\times3}{12\times3}=\dfrac{-21}{36};\dfrac{11}{-18}=\dfrac{-11}{18}=\dfrac{-11\times2}{18\times2}=\dfrac{-22}{36}\)
Vì \(\dfrac{-21}{36}>\dfrac{-22}{36}=>\dfrac{7}{-12}>\dfrac{11}{-18}\)
