Bài toán 6 : Bỏ ngoặc và tính.
a. -|-12| – (-5 + |-4| -12) + (-9)
k. 24 – (72 – 13 + 24) – (72 – 13)
b. –(-15) – (-3 + 7 – 8 ) – |-5|
l. |4 – 9 – 5| – (4 – 9 – 5) – 15 + 9
c. |11 – 13| – ( -12 + 20 – 8 – 10)
m. -20 – (25 – 11 + 8) + (25 – 8 + 20)
d. (-40) + (-13) + 40 + (-13)
n. |-5 + 7 – 8| – ( -5 + 7 – 8)
e. (+23) + (-12) + |5|.2
o. (-20 + 10 – 3) – (-20 + 10) + 27
f. (-5) + (-15) + |-8| + (-8)
p. 13 – [5 – (4 – 5) + 6] – [3 – (2 – 7)]
g. 5 – (4 – 7 + 12) + (4 – 7 + 12)
q. (14 – 12 – 7) – [-(-3 + 2) + (5 – 9)]
h. -|-5 + 3 – 7| – |-5 + 7|
r. 14 – 23 + (5 – 14) – (5 – 23) + 17
( giải chi tiết
Đáp án:
`a. -|-12| – (-5 + |-4| -12) + (-9)`
` = -12 +5 – 4 +12 + (-9)`
` = (-12+12)+(5-4)+(-9)`
`= 0 +1+(-9)`
`= -8`
`k. 24 – (72 – 13 + 24) – (72 – 13)`
`= 24 – 72 +13 -24 – 72 +13`
`= (24-24) + (-72 +13)+(-72+13)`
`= 0 -59 – 59 `
`= -118`
`b. –(-15) – (-3 + 7 – 8 ) – |-5|`
`= 15 +3 – 7 +8 – 5`
`= (15-5) + (3+8-7)`
`= 10 + 4`
`= 14`
`l. |4 – 9 – 5| – (4 – 9 – 5) – 15 + 9`
`= 10 – 4 +9+5 – 15-9`
`= (10+5-15 ) + (9-9) – 4`
`= 0+0+4 = 4`
`c. |11 – 13| – ( -12 + 20 – 8 – 10)`
`= 2 -12 -20 +8+10`
`= (2+8+10-20)-12`
`= 0 -12 =-12`
`m. -20 – (25 – 11 + 8) + (25 – 8 + 20)`
`= -20 – 25 +11-8 +25 – 8 +20`
`= (-20+20) + (-25+25) + 11-8-8`
`= 0 + 0 -5 = -5`
`d. (-40) + (-13) + 40 + (-13)`
`= -40 +40 -13-13`
`= 0 – 26 = -26`
`n. |-5 + 7 – 8| – ( -5 + 7 – 8)`
`= 6 +6`
`=12`
`e. (+23) + (-12) + |5|.2`
`= 23 -12 +10“
`= 21`
`o, (-20 + 10 – 3) – (-20 + 10) + 27`
`= -13 +10 +27`
`= 24`
`f. (-5) + (-15) + |-8| + (-8)`
`= -20 + 8 +-8`
`= -20`
`p. 13 – [5 – (4 – 5) + 6] – [3 – (2 – 7)]`
`= 13 – 12 – 8`
`= -7`
`g. 5 – (4 – 7 + 12) + (4 – 7 + 12)`
`= 5 – 9 + 9`
`= 5`
`q. (14 – 12 – 7) – [-(-3 + 2) + (5 – 9)]`
`= -5 +3`
`= -2`
`h. -|-5 + 3 – 7| – |-5 + 7|`
`= -9 – 2`
`=-11`
`r. 14 – 23 + (5 – 14) – (5 – 23) + 17`
`= 14-23 + 5-14 – 5 +23 +17`
`= (14-14)+(-23+23) +(5-5) +17`
`=17`
`Go od luck!`