`#3107.101107`
`1)`
\(C=\dfrac{5}{18}+\dfrac{8}{19}-\dfrac{7}{21}+\left(\dfrac{-10}{36}+\dfrac{11}{19}+\dfrac{1}{3}\right)-\dfrac{5}{8}\)
`= 5/18 + 8/19 - 1/3 - 5/18 + 11/19 + 1/3 - 5/8`
`= (5/18 - 5/18) + (1/3 - 1/3) + (8/19 + 11/19) - 5/8`
`= 19/19 - 5/8`
`= 1 - 5/8`
`= 3/8`
Vậy, `C = 3/8`
`2)`
`E =`\(\dfrac{1}{13}+\left(-\dfrac{5}{18}-\dfrac{1}{13}+\dfrac{12}{17}\right)-\left(\dfrac{12}{17}-\dfrac{5}{18}+\dfrac{7}{5}\right)\)
`= 1/13 - 5/18 - 1/13 + 12/17 - 12/17 + 5/18 - 7/5`
`= (1/13 - 1/13) + (-5/18 + 5/18) + (12/17 - 12/17) - 7/5`
`= -7/5`
Vậy, `E = -7/5`
`3)`
\(F=\dfrac{15}{14}-\left(\dfrac{17}{23}-\dfrac{80}{87}+\dfrac{5}{4}\right)+\left(\dfrac{17}{23}-\dfrac{15}{14}+\dfrac{1}{4}\right)\)
`= 15/14 - 17/23 + 80/87 - 5/4 + 17/23 - 15/14 + 1/4`
`= (15/14 - 15/14) + (-17/23 + 17/23) + (-5/4 + 1/4) + 80/87`
`= -4/4 + 80/87`
`= -1 + 80/87`
`= -7/87`
Vậy, `F = -7/87`
`4)`
\(G=\dfrac{1}{25}-\dfrac{4}{27}+\left(-\dfrac{23}{27}+\dfrac{-1}{25}-\dfrac{5}{43}\right)+\dfrac{5}{43}-\dfrac{4}{7}\)
`= 1/25 - 4/27 - 23/27 - 1/25 - 5/43 + 5/43 - 4/7`
`= (1/25 - 1/25) - (4/27 + 23/27) + (-5/43 + 5/43) - 4/7`
`= -27/27 - 4/7`
`= -1 - 4/7`
`= -11/7`
Vậy, `G = -11/7.`
\(1.C=\dfrac{5}{18}+\dfrac{8}{19}-\dfrac{7}{21}+\left(\dfrac{-10}{36}+\dfrac{11}{19}+\dfrac{1}{3}\right)-\dfrac{5}{8}\\ =\dfrac{5}{18}+\dfrac{8}{19}-\dfrac{1}{3}+\dfrac{-5}{18}+\dfrac{11}{19}+\dfrac{1}{3}-\dfrac{5}{8}\\ =\left(\dfrac{5}{18}-\dfrac{5}{18}\right)+\left(\dfrac{8}{19}+\dfrac{11}{19}\right)+\left(\dfrac{1}{3}-\dfrac{1}{3}\right)-\dfrac{5}{8}\\ =1-\dfrac{5}{8}\\ =\dfrac{3}{8}\\ 2.E=\dfrac{1}{13}+\left(\dfrac{-5}{18}-\dfrac{1}{13}+\dfrac{12}{17}\right)-\left(\dfrac{12}{17}-\dfrac{5}{18}+\dfrac{7}{5}\right)\\ =\dfrac{1}{13}-\dfrac{5}{18}-\dfrac{1}{13}+\dfrac{12}{17}-\dfrac{12}{17}+\dfrac{5}{18}-\dfrac{7}{5}\\ =\left(\dfrac{1}{13}-\dfrac{1}{13}\right)+\left(\dfrac{5}{18}-\dfrac{5}{18}\right)+\left(\dfrac{12}{17}-\dfrac{12}{17}\right)-\dfrac{7}{5}\\ =-\dfrac{7}{5}\\ 3.F=\dfrac{15}{14}-\left(\dfrac{17}{23}-\dfrac{80}{87}+\dfrac{5}{4}\right)+\left(\dfrac{17}{23}-\dfrac{15}{14}+\dfrac{1}{4}\right)\)
\(=\dfrac{15}{14}-\dfrac{17}{23}+\dfrac{80}{87}-\dfrac{5}{4}+\dfrac{17}{23}-\dfrac{15}{14}+\dfrac{1}{4}\\=\left(\dfrac{15}{14}-\dfrac{15}{14}\right)+\left(\dfrac{17}{23}-\dfrac{17}{23}\right)+\left(-\dfrac{5}{4}+\dfrac{1}{4}\right)+\dfrac{80}{87}\\ =-1+\dfrac{80}{87}\\ =-\dfrac{7}{87}\\ 4.G=\dfrac{1}{25}-\dfrac{4}{27}+\left(\dfrac{-23}{27}+\dfrac{-1}{25}-\dfrac{5}{43}\right)+\dfrac{5}{43}-\dfrac{4}{7}\\ =\dfrac{1}{25}-\dfrac{4}{27}+\dfrac{-23}{27}-\dfrac{1}{25}-\dfrac{5}{43}+\dfrac{5}{43}-\dfrac{4}{7}\\ =\left(\dfrac{1}{25}-\dfrac{1}{25}\right)+\left(\dfrac{5}{43}-\dfrac{5}{43}\right)+\left(\dfrac{-4}{27}-\dfrac{23}{27}\right)-\dfrac{4}{7}\\ =-1-\dfrac{4}{7}\\ =\dfrac{-11}{7}\)
1) C = \(\dfrac{5}{18}+\dfrac{8}{19}-\dfrac{7}{21}+\left(\dfrac{-10}{36}+\dfrac{11}{19}+\dfrac{1}{3}\right)-\dfrac{5}{8}\)
C = \(\dfrac{5}{18}+\dfrac{8}{19}-\dfrac{7}{21}+\left(\dfrac{-5}{18}+\dfrac{11}{19}+\dfrac{1}{3}\right)-\dfrac{5}{8}\)
C = \(\dfrac{5}{18}+\dfrac{8}{19}-\dfrac{1}{3}+\left(\dfrac{-95}{342}+\dfrac{198}{342}+\dfrac{114}{342}\right)-\dfrac{5}{8}\)
C = \(\dfrac{5}{18}+\dfrac{8}{19}-\dfrac{1}{3}+\dfrac{217}{342}-\dfrac{5}{8}\)
C = \(\dfrac{380}{1368}+\dfrac{576}{1368}-\dfrac{456}{1368}+\dfrac{868}{1368}-\dfrac{855}{1368}\)
C = \(\dfrac{513}{1368}=\dfrac{3}{8}\)
