题目内容
计算(1)(-2)2-|-7|+3-2×(-| 1 |
| 2 |
(2)-36×(
| 1 |
| 9 |
| 1 |
| 6 |
| 1 |
| 18 |
(3)-16-(1-0.5)×
| 1 |
| 3 |
(4)(-3)2008×(
| 1 |
| 3 |
分析:(1)先去掉绝对值符号,再根据有理数的混合运算顺序计算;
(2)利用乘法分配律简便运算;
(3)根据有理数混合运算的顺序,先算乘方再算乘除最后算加减,有括号的先算括号里面的;
(4)根据积的乘方的性质的逆用即进行计算.
(2)利用乘法分配律简便运算;
(3)根据有理数混合运算的顺序,先算乘方再算乘除最后算加减,有括号的先算括号里面的;
(4)根据积的乘方的性质的逆用即进行计算.
解答:解:(1)(-2)2-|-7|+3-2×(-
)
=4-7+3+1
=8-7
=1;
(2)-36×(
-
-
)
=
×(-36)-
×(-36)-
×(-36)
=-4+6+2
=-4+8
=4;
(3)-16-(1-0.5)×
×[2-(-3)2]
=-1-
×
×(2-9)
=-1+
=
;
(4)(-3)2008×(
)2009-12008-(-1)2008
=(-3)2008×(
)2008×
-1-1
=(-3×
)2008×
-2
=
-2
=-
.
| 1 |
| 2 |
=4-7+3+1
=8-7
=1;
(2)-36×(
| 1 |
| 9 |
| 1 |
| 6 |
| 1 |
| 18 |
=
| 1 |
| 9 |
| 1 |
| 6 |
| 1 |
| 18 |
=-4+6+2
=-4+8
=4;
(3)-16-(1-0.5)×
| 1 |
| 3 |
=-1-
| 1 |
| 2 |
| 1 |
| 3 |
=-1+
| 7 |
| 6 |
=
| 1 |
| 6 |
(4)(-3)2008×(
| 1 |
| 3 |
=(-3)2008×(
| 1 |
| 3 |
| 1 |
| 3 |
=(-3×
| 1 |
| 3 |
| 1 |
| 3 |
=
| 1 |
| 3 |
=-
| 5 |
| 3 |
点评:本题信息量比较大,主要考查有理数的混合运算、乘法分配律和积的乘方的性质的逆用,熟练掌握混合运算的顺序是解题的关键,使用运算定律使运算更加简便.
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