题目内容
计算:
(1)-40-28-(-19)+(-24)
(2)
×(
-
)×
÷
(3)-14-
×[3-(-3)2]
(4)-12+33×(1-
)+(-2)2.
(1)-40-28-(-19)+(-24)
(2)
| 7 |
| 6 |
| 1 |
| 6 |
| 1 |
| 3 |
| 3 |
| 14 |
| 3 |
| 5 |
(3)-14-
| 1 |
| 6 |
(4)-12+33×(1-
| 2 |
| 3 |
分析:(1)先化简,再相加即可求解;
(2)先算小括号里面的减法,再算括号外面的乘除法;
(3)(4)按照有理数混合运算的顺序,先乘方后乘除最后算加减,有括号的先算括号里面的.
(2)先算小括号里面的减法,再算括号外面的乘除法;
(3)(4)按照有理数混合运算的顺序,先乘方后乘除最后算加减,有括号的先算括号里面的.
解答:解:(1)-40-28-(-19)+(-24)
=-40-28+19-24
=-92+19
=-73;
(2)
×(
-
)×
÷
=
×(-
)×
×
=-
;
(3)-14-
×[3-(-3)2]
=-1-
×[3-9]
=-1-
×(-6)
=-1+1
=0;
(4)-12+33×(1-
)+(-2)2.
=-1+27×
+4
=-1+9+4
=12.
=-40-28+19-24
=-92+19
=-73;
(2)
| 7 |
| 6 |
| 1 |
| 6 |
| 1 |
| 3 |
| 3 |
| 14 |
| 3 |
| 5 |
=
| 7 |
| 6 |
| 1 |
| 6 |
| 3 |
| 14 |
| 5 |
| 3 |
=-
| 5 |
| 72 |
(3)-14-
| 1 |
| 6 |
=-1-
| 1 |
| 6 |
=-1-
| 1 |
| 6 |
=-1+1
=0;
(4)-12+33×(1-
| 2 |
| 3 |
=-1+27×
| 1 |
| 3 |
=-1+9+4
=12.
点评:本题考查的是有理数的运算能力.注意:
(1)要正确掌握运算顺序,在混合运算中要特别注意运算顺序:先三级,后二级,再一级;有括号的先算括号里面的;同级运算按从左到右的顺序;
(2)去括号法则:--得+,-+得-,++得+,+-得-.
(1)要正确掌握运算顺序,在混合运算中要特别注意运算顺序:先三级,后二级,再一级;有括号的先算括号里面的;同级运算按从左到右的顺序;
(2)去括号法则:--得+,-+得-,++得+,+-得-.
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