题目内容
计算:(1)-6+(-4)-(-2)
(2)(-
| 1 |
| 3 |
| 2 |
| 5 |
| 2 |
| 3 |
(3)(-
| 3 |
| 7 |
| 1 |
| 3 |
(4)|-2
| 1 |
| 4 |
| 1 |
| 3 |
(5)(-30)×(
| 1 |
| 3 |
| 5 |
| 6 |
| 3 |
| 10 |
(6)-3-[-5+(1-
| 1 |
| 2 |
| 1 |
| 5 |
分析:(1)先去括号,再按照从左到右的顺序计算即可,特别要注意符号的变化;
(2)先去括号,再把各分式通分,把小数化为分数,再按照从左到右的顺序计算即可;
(3)先把小数化为分数,再按照从左到右的顺序计算即可;
(4)先去绝对值号,再算乘除法;
(5)先把括号内的分式通分,再算乘法;
(6)先算小括号内的计算,再去大括号,最后算减法.
(2)先去括号,再把各分式通分,把小数化为分数,再按照从左到右的顺序计算即可;
(3)先把小数化为分数,再按照从左到右的顺序计算即可;
(4)先去绝对值号,再算乘除法;
(5)先把括号内的分式通分,再算乘法;
(6)先算小括号内的计算,再去大括号,最后算减法.
解答:解:(1)原式=-6-4+2=-10+2=-8;
(2)原式=-
+
-
+
=-1+
+
=0;
(3)原式=(-
)×
×(-
)×(-8)=1×(-1)=-1;
(4)原式=
×(-
)×
=(-
)×
=-
;
(5)原式=(-30)×(
-
-
)=(-30)×(-
-
)=(-30)×(-
-
)=(-30)×(-
)=24;
(6)原式=-3-[-5+(1-
)×(-
)]=-3-[-5+
×(-
)]=-3-[-5-
]=-3+5+
=2
.
(2)原式=-
| 1 |
| 3 |
| 2 |
| 5 |
| 2 |
| 3 |
| 3 |
| 5 |
| 2 |
| 5 |
| 3 |
| 5 |
(3)原式=(-
| 3 |
| 7 |
| 1 |
| 8 |
| 7 |
| 3 |
(4)原式=
| 9 |
| 4 |
| 1 |
| 3 |
| 1 |
| 3 |
| 3 |
| 4 |
| 1 |
| 3 |
| 1 |
| 4 |
(5)原式=(-30)×(
| 2 |
| 6 |
| 5 |
| 6 |
| 3 |
| 10 |
| 1 |
| 2 |
| 3 |
| 10 |
| 5 |
| 10 |
| 3 |
| 10 |
| 8 |
| 10 |
(6)原式=-3-[-5+(1-
| 3 |
| 5 |
| 1 |
| 2 |
| 2 |
| 5 |
| 1 |
| 2 |
| 1 |
| 5 |
| 1 |
| 5 |
| 1 |
| 5 |
点评:本题考查了有理数的混合运算,解题的关键是熟练掌握运算顺序,此题比较简单,但计算时要特别细心,不然很容易出错.
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