Đáp án:
`a, (-1/2) - (-3/5) + (-1/9) + 1/71 - (-2/7) + 4/35 - 7/18`
`= -1/2 + 3/5 - 1/9 + 1/71 + 2/7 + 4/35 - 7/18`
`= -9/18 + 21/35 - 2/18 + 1/71 + 10/35 + 4/35 - 7/18`
`= (-9/18 - 2/18 - 7/18) + (21/35 + 4/35 + 10/35) + 1/71`
`= -18/18 + 35/35 + 1/71`
`= - 1 + 1 + 1/71`
`= 0 + 1/71 = 1/71`
`b, ( 5 + 1/5 - 2/9) - (2 - 1/23 -2 3/35 + 5/6) - (8 + 2/7 - 1/18)`
`= 5 + 1/5 - 2/9 - 2 + 1/23 + 2 3/35 - 5/6 - 8 - 2/7 + 1/18`
`= 5 + 1/5 - 2/9 - 2 + 1/23 + 73/35 - 5/6 - 8 - 2/7 + 1/18`
`= (5 - 2 - 8) + 7/35 - 4/18 + 1/23 + 73/35 - 15/18 - 10/35 + 1/18`
`= - 5 + (7/35 + 73/35 - 10/35) + (-4/18 - 15/18 + 1/18) +1/23`
`= -5 + 70/35 + -18/18 + 1/23`
`= -5 + 2 - 1 + 1/23 = -4 + 1/23`
`= -92/23 + 1/23 = -91/23`
`c, (-5/9).3/11 + (-13/18) .3/11`
`= 3/11 (-5/9 - 13/18)`
`= 3/11 (-10/18 - 13/18)`
`= 3/11 . (-23/18)`
`= (3.(-23))/(11.18)`
`= -23/66`
`d, (-1/4): (-13/2) - 7/24 . (-2/13)`
`= -1/4 . 2/(-13) - (7. (-2))/24.13`
`= (-1.2)/(4.(-13)) - (-7/156)`
`= 1/26 + 7/156`
`= 6/156 + 7/156`
`= 8/156 = 1/12`
`e, (5/7 - 7/5) - [1/2 - (-2/7 - 1/10)]`
`= 5/7 - 7/5 - [1/2 + 2/7 + 1/10]`
`= 5/7 - 7/5 - 1/2 - 2/7 - 1/10`
`= (5/7 - 2/7) - 14/10 - 5/10 - 1/10`
`= 3/7 - (14/10 + 5/10 + 1/10)`
`= 3/7 - 20/10 = 3/7 - 2`
`= -11/7`
`f, 7.5 : (-5)/4 + 2 1/2 : (-5)/4`
`= 7,5 . (-4)/5 + 2,5 . (-4/5)`
`= (-4)/5 (7,5 + 2,5)`
`= (-4)/5 . 10`
`= -8`
`g, (8^10 + 4^10)/(8^4 + 4^11)`
`= ((2^3)^10 + (2^2)^10)/((2^3)^4 + (2^2)^11)`
`= (2^30 + 2^20)/(2^12 + 2^22)`
`= (2^20(2^10+ 1))/(2^12(1 + 2^10))`
`= 2^8 = 256`
`h, 2^3 +3.(1/2)^0 . [(-2)^2 : 1/2].8`
`= 8 + 3.1 .[4 . 2/1] . 8`
`= 8 + 3.8.8`
`= 8 + 192`
`= 200`
`i, 5/12` . $\sqrt{64}$ - $\frac{\sqrt{49}}{3}$ + $\frac{6}{\sqrt{81}}$
`= 5/12. 8 - 7/3 + 6/9`
`= (5.8)/12 - 7/3 + 2/3`
`= 10/3 - (7/3 - 2/3)`
`= 10/3 - 5/3`
`= 5/3`
`l, 5. |(-1)/10 + 7/15| - 2/13 . 4 1/3`
`= 5.|(-3)/30 + 14/30| - 2/13. 13/3`
`= 5.| 11/30 | - (2.13)/(13.3)`
`= 5.11/30 - 2/3`
`= 11/6 - 2/3 = 11/6 - 4/6`
`= 7/6`
Học tốt
