Đáp án:
\(A = - \dfrac{5}{2}\)
Giải thích các bước giải:
\(\begin{array}{l}
C1:A = \left( {\dfrac{{3 - 2.6 + 4}}{6}} \right) - \left( {\dfrac{{7.6 + 3 - 4}}{6}} \right) - \left( {\dfrac{{3 - 4 - 5.6}}{6}} \right)\\
= \dfrac{{ - 5}}{6} - \dfrac{{41}}{6} - \dfrac{{ - 31}}{6}\\
= \dfrac{{ - 5 - 41 + 31}}{6} = - \dfrac{{15}}{6} = - \dfrac{5}{2}\\
C2:A = \dfrac{1}{2} - 2 + \dfrac{2}{3} - 7 - \dfrac{1}{2} + \dfrac{2}{3} - \dfrac{1}{2} + \dfrac{2}{3} + 5\\
= \left( { - 2 - 7 + 5} \right) + \left( {\dfrac{1}{2} - \dfrac{1}{2} - \dfrac{1}{2}} \right) + \left( {\dfrac{2}{3} + \dfrac{2}{3} + \dfrac{2}{3}} \right)\\
= - 4 - \dfrac{1}{2} + 3 = - 1 - \dfrac{1}{2} = - \dfrac{5}{2}
\end{array}\)
