\(=\left(6-\dfrac{2}{3}+\dfrac{1}{2}\right)-\left(5+\dfrac{5}{3}-\dfrac{3}{2}\right)-\left(3-\dfrac{7}{3}+\dfrac{5}{2}\right)\)
\(=\left(\dfrac{16}{3}+\dfrac{1}{2}\right)-\left(\dfrac{20}{3}-\dfrac{3}{2}\right)-\left(\dfrac{2}{3}+\dfrac{5}{2}\right)\)
\(=\dfrac{35}{6}-\dfrac{31}{6}-\dfrac{19}{6}\)
\(=\dfrac{2}{3}-\dfrac{19}{6}\)
\(=\dfrac{-15}{6}\)
(163+12)−(203−32)−(23+52)=(163+12)−(203−32)−(23+52)
23−196=23−196
Lời giải:
\(a=6-\frac{2}{3}+\frac{1}{2}-5-\frac{5}{3}+\frac{3}{2}-3+\frac{7}{3}-\frac{5}{2}\)
\(=(6-5-3)+(\frac{7}{3}-\frac{2}{3}-\frac{5}{3})+(\frac{1}{2}+\frac{3}{2}-\frac{5}{2})=-2+0+\frac{-1}{2}=-(2+\frac{1}{2})=\frac{-5}{2}\)
