a, \(\dfrac{3}{4}+\dfrac{-5}{24}=\dfrac{18}{24}+\dfrac{-5}{24}=\dfrac{13}{24}\)

b, \(\dfrac{-3}{5}+\dfrac{1}{15}=\dfrac{-9}{15}+\dfrac{1}{15}=\dfrac{-8}{15}\)

c, \(\dfrac{-5}{6}+\dfrac{1}{12}=\dfrac{-10}{12}+\dfrac{1}{12}=\dfrac{-9}{12}=\dfrac{-3}{4}\)

\(\dfrac{-13}{12}\) không rút gọn được nữa nhé !

a, \(\dfrac{1}{6}+\dfrac{1}{3}=\dfrac{1}{6}+\dfrac{2}{6}=\dfrac{3}{6}=\dfrac{1}{2}\)

b, \(\dfrac{1}{4}+\dfrac{1}{8}=\dfrac{2}{8}+\dfrac{1}{8}=\dfrac{3}{8}\)

c, \(\dfrac{-5}{12}+\dfrac{2}{-3}=\dfrac{-5}{12}+\dfrac{-8}{12}=\dfrac{-13}{12}\)

số đối của \(\dfrac{-3}{-4}\) là \(-\dfrac{3}{4}\) nhé.

số đối của -3 là 3 nhé