Bài 2: Bỏ ngoặc rồi tính
1/-7264 +(1543 +7264)
21 (144-97)- 144
3/ (-145)- (18- 145)
4/ 111+(-11+ 27)
5/ (27 +514) – (486-73)
6/ (36+79) +(145- 79-36)
71 10-(12-(-9-1)]
8/ (38 – 29 + 43)-(43+38)
9/ 271-[(-43)+271- (-17)]
10/-144-129-(+144)-(+144)]
Đáp án:
Giải thích các bước giải:
1,-7264+8807=1543
2,17-114=-97
3,-145-18+145=-18
4,111-11+27=127
,5,541-413=128
6,115+30=145
7,10-12-10=-12
8,52-81=_29
9,271-245=26
10,-144-129-144-144=-561
Đáp án:
1) `-7264+(1543+7264)`
`= -7264+1543+7264`
`= 1543`
2) `(144 – 97) – 144`
`= 144-97-144`
`= -97`
3) `(-145) – (18 – 145)`
`= -145-18+145`
`= -18`
4) `111 + (-11 + 27)`
`= 111+-11+27`
`= 100+27=127`
5) `(27 + 514) – (486 – 73)`
`= 27+514-486+73`
`= (27+73)+(514-486)`
`= 100+28=128`
6) `(36 + 79) + (145 – 79 – 36)`
`= 36+79+145-79-36`
`= 145`
7) `10 – [12 -(- 9 – 1)]`
`= 10-[12+9+1]`
`= 10-12-9-1`
`= -12`
8) `(38 – 29 + 43) – (43 + 38)`
`= 38-29+43-43-38`
`= -29`
9) `271 – [(-43) + 271 – (-17)]`
`= 271+43-271-17`
`= 43-17=26`
10) `-144 – [29 – 144 – 144]`
`= -144-29+144+144`
`= -29+144=155`