Bài 2: Bỏ ngoặc rồi tính
1/ -7264 + (1543 + 7264)
2/ (144 – 97) – 144
3/ (-145) – (18 – 145)
4/ 111 + (-11 + 27)
5/ (27 + 514) – (486 – 73)
6/ (36 + 79) + (145 – 79 – 36)
7/ 10 – [12 – (- 9 – 1)]
8/ (38 – 29 + 43) – (43 + 38)
9/ 271 – [(-43) + 271 – (-17)]
10/ -144 – [29 – (+144) – (+144)]
1/ -7264 + (1543 + 7264) = -7264 +1543 +7264
= (-7264 +7264) +1543
= 0 + 1543 = 1543
2/ (144 – 97) – 144 = 144 -97 -144
= (144 -144) -97
= 0 -97
= -97
3/ (-145) – (18 – 145) = -145 -18 +145
= (-145 +145) -18
= 0 -18
= -18
4/ 111 + (-11 + 27) = 111 -11 +27
= 100 +27
= 127
5/ (27 + 514) – (486 – 73) = 27 +514 -486 -73
= 541 -486 -73
= 55 -73
= -18
6/ (36 + 79) + (145 – 79 – 36) = 36 +79 +145 -79 -36
= (36 -36) + (79 -79) +145
= 0 + 0 +145
= 145
7/ 10 – [12 – (- 9 – 1)] = 10 -(12 +9 +1)
= 10 -12 -9 -1
= (10 -9 -1) -12
= (1 -1) -12
= 0 -12
= -12
8/ (38 – 29 + 43) – (43 + 38) = 38 -29 +43 -43 -38
= (38 -38) + (43 -43) -29
= 0 + 0 -29
= -29
9/ 271 – [(-43) + 271 – (-17)] = 271 +43 -271 -17
= (271 -271) + (43 -17)
= 0 + 26
= 26
10/ -144 – [29 – (+144) – (+144)] = -144 -(29 -144 -144)
= -144 -29 +144 +144
= (-144 +144 +144) -29
= 144 -29
= 115
1/ -7264 + (1543 + 7264)
= -7264 + 1543 + 7264
= ( – 7264 + 7264 ) + 1543
= 0 + 1543
= 1543
2/ (144 – 97 ) – 144
= 144 – 97 – 144
= (144-144) -97
= 0 – 97
= -97
3/ ( -145 ) – ( 18 – 145 )
= (-145) – 18 + 145
= ( – 145 + 145 ) – 18
= 0 – 18
= – 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 + 514 – 486
= 614 – 486
= 128
6/ ( 36 + 79 ) + ( 145 – 79 – 36 )
= 36 + 79 + 145 – 79 – 36
= ( 36 – 36 ) + ( 79 – 79 ) + 145
= 0 + 0 + 145
= 145
7/ 10 – [ 12 – ( – 9 – 1 ) ]
= 10 – [ 12 + 9 + 1 ]
= 10 – 12 – 9 – 1
= 10 + ( -12 ) – 9 – 1
= – ( 12 – 10 ) – 9 – 1
= – 2 – 9 – 1
= – 11 – 1 ( lười quá nên trừ luôn nha )
= – 12
8/ ( 38 – 29 + 43 ) – ( 43 + 38 )
= 38 – 39 + 43 – 43 – 38
= ( 38 – 38 ) + ( 43 – 43 ) – 39
= 0 + 0 – 39
= – 39
9/ 271 – [ ( – 43 ) + 271 – ( – 17 ) ]
= 271 + 43 – 271 + 17
= ( 271 – 271 ) + ( 43 + 17 )
= 0 + 60
= 60
10/ – 144 – [ 29 – ( + 144 ) – ( + 144 )
= – 144 – 29 + ( – 144 ) + ( – 144 )
= – 144 – 29 – 144 – 144
= – 173 – 144 – 144 ( lại lười tính kĩ tiếp :v )
= – 317 – 144
= – 317 + ( – 144 )
= – 461
Chúc bạn học tốt!
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