Question

quy đồng 

Answer 1

\(c,\dfrac{2}{5}=\dfrac{2\times3}{5\times3}=\dfrac{6}{15}\)

\(\dfrac{4}{15}\)

\(\dfrac{-1}{3}=\dfrac{-1\times5}{3\times5}=\dfrac{-5}{15}\)

\(d,\dfrac{-3}{8}=\dfrac{-3\times3}{8\times3}=\dfrac{-9}{24}\\ \dfrac{-2}{3}=\dfrac{-2\times8}{3\times8}=\dfrac{-16}{24}\\ \dfrac{3}{24}\)

Answer 2

c.6/15;4/15;-5/15

d.-9/24;-16/24;3/24

Answer 3

\(c)\)

\(MSC:15\)

\(\dfrac{2}{5}\)=\(\dfrac{2.3}{5.3}\)=\(\dfrac{6}{15}\)

\(\dfrac{4}{15}\)

\(\dfrac{-1}{3}\)=\(\dfrac{-1.5}{3.5}\)=\(\dfrac{-5}{15}\)

\(d)\)

\(MSC:24\)

\(\dfrac{-3}{8}\)=\(\dfrac{-3.3}{8.3}\)=\(\dfrac{-9}{24}\)

\(\dfrac{-2}{3}\)=\(\dfrac{-2.8}{3.8}\)=\(\dfrac{-16}{24}\)

\(\dfrac{3}{24}\)