\(a,8:\left(\dfrac{1}{3}-\dfrac{1}{2}\right)^3=8:\left(\dfrac{2}{6}-\dfrac{3}{6}\right)^3=8:\left(-\dfrac{1}{6}\right)^3=8:\dfrac{-1}{216}=8.-\dfrac{216}{1}=\dfrac{-1728}{1}=-1728\)
\(b,6,75+\dfrac{-1}{8}+\dfrac{1}{4}-5.\dfrac{-3}{8}=\dfrac{27}{4}+\dfrac{-1}{8}+\dfrac{1}{4}-\left(-\dfrac{15}{8}\right)=\dfrac{54}{8}+\dfrac{-1}{8}+\dfrac{2}{8}+\dfrac{15}{8}=\dfrac{70}{8}=\dfrac{35}{4}\)
8 : (1/3 - 1/2)^3`
`= 8 : (-1/6)^3`
`= 8 : (-1/216)`
`= 8 xx (-216)`
`= -1728`
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`6,75 + (-1/2)^3 + 0,5^2 - 5 . -3/8`
`= 27/4 + (-1/8) + 1/4 - (-15/8)`
`= 27/4 + (-1/8) + 1/4 + 15/8`
`= 53/8 + 1/4 + 15/8`
`= 55/8 + 15/8`
`= 35/4`
