Bỏ ngoặc rồi tính 1) 10 – [12 – (-9 – 1)] 2) (38 – 29 + 43) – (43 + 38) 3) 271 – [(-43) + 271 – (-17)] 4) -144 – [29 – (+144) – (+144)]

0 bình luận về “Bỏ ngoặc rồi tính 1) 10 – [12 – (-9 – 1)] 2) (38 – 29 + 43) – (43 + 38) 3) 271 – [(-43) + 271 – (-17)] 4) -144 – [29 – (+144) – (+144)]”

1. `1)10-[12-(-9-1)]`

   `=10-(12+9 + 1)`

   `=10-(10+12)`

   `=10 – 10 – 12`

   `=-12`

   `2)(38-29+43)-(43+38)`

   `= 38 + (-29) + 43 + (-43) + (-38)`

   `= [38 + (-38)] + [43 + (-43)] + (-29)`

   `= -29`

   `3) 271 – [(-43) + 271 – (-17)]`

   `=271+43-271-17`

   `=(271-271)+(43-17)`

   `=26`

   `4)-144 – [29 – (+144) – (+144)]`

   `=-144-29+144+144`

   `=(-144+144+144)-29`

   `=115`

    

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2. Đáp án:

   1) -12

   2) -29

   3) 26

   4) 115

   Giải thích các bước giải:

   1) 10 – [12 – (-9 – 1)]

   = 10 – (12 + 9 + 1)

   = 10 – (10 + 12)

   =10 – 10 – 12

   = (10 – 10) – 12

   = 0 – 12

   = -12

   2) (38 – 29 + 43) – (43 + 38)

   = 38 + (-29) + 43 + (-43) + (-38)

   = [38 + (-38)] + [43 + (-43)] + (-29)

   = 0 + 0 + (-29)

   = -29

   3) 271 – [(-43) + 271 – (-17)]

   = 271 – (-43 + 271 + 17)

   = 217 + 43 – 271 -17

   = (217 – 217) + (43 – 17)

   = 0 + 26

   = 26

   4) -144 – [29 – (+144) – (+144)]

   = -144 – (29 – 144 – 144)

   = -144 – 29 +144 + 144

   = (-144 + 144) – 29 + 144

   = 0 – 29 +144

   = -29 +144

   = 115

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