(-21/43 + 12/57) : -3/7 + (45/57 + -22/43) : -3/7

Đáp án:

 `(-\frac{21}{43}+\frac{12}{57}):\frac{-3}{7}+(\frac{45}{57}+\frac{-22}{43}):\frac{-3}{7}`

`= (\frac{-21}{43}+\frac{12}{57}).\frac{-7}{3}+(\frac{45}{57}+\frac{-22}{43}).\frac{-7}{3}`

`=(-\frac{7}{3}).(\frac{-21}{43}+\frac{12}{57}+\frac{45}{57}+\frac{-22}{43})`

`= (-\frac{7}{3}).[(\frac{-21}{43}+\frac{-22}{43})+(\frac{12}{57}+\frac{45}{57})]`

`=(-\frac{7}{3}).(\frac{-43}{43}+\frac{57}{57})`

`=(-\frac{7}{3}).[(-1)+1]`

`=(-\frac{7}{3}).0`

`=0`