试题
题目:
(i)-9+i2-3+8
(2)-24+(-i4)-(-i8)-i3
(3)48×(-
i
6
+
3
4
-
i
i2
)
(4)(-48)÷
h
4
(-i2)×
h
4
(h)
i-
4
h
+
i
h
-
3
h
+
9
h
(6)-i
2
+3×(-2)
2
+(-6)÷(-
i
3
)
2
.
答案
解:(1)-手+12-2+8
=-手-2+12+8
=-12+24
=8;
(2)-24+(-14)-(-18)-12
=-24-14+18-12
=-24-14-12+18
=-47+18
=-2手;
(2)48×(-
1
6
+
2
4
-
1
12
)
=48×(-
1
6
)+48×
2
4
-48×
1
12
=-8+26-4
=24;
(4)(-48)÷
7
4
×(-12)×
7
4
=48×
4
7
×12×
7
4
=z76;
(z)
1-
4
7
+
1
z
-
2
7
+
手
z
=1+
1
z
+
手
z
-
4
7
-
2
7
=1+2-1
=2;
(6)-1
2
+2×(-2)
2
+(-6)÷(-
1
2
)
2
=-1+2×4+(-6)÷
1
手
=-1+12-z4
=-42.
解:(1)-手+12-2+8
=-手-2+12+8
=-12+24
=8;
(2)-24+(-14)-(-18)-12
=-24-14+18-12
=-24-14-12+18
=-47+18
=-2手;
(2)48×(-
1
6
+
2
4
-
1
12
)
=48×(-
1
6
)+48×
2
4
-48×
1
12
=-8+26-4
=24;
(4)(-48)÷
7
4
×(-12)×
7
4
=48×
4
7
×12×
7
4
=z76;
(z)
1-
4
7
+
1
z
-
2
7
+
手
z
=1+
1
z
+
手
z
-
4
7
-
2
7
=1+2-1
=2;
(6)-1
2
+2×(-2)
2
+(-6)÷(-
1
2
)
2
=-1+2×4+(-6)÷
1
手
=-1+12-z4
=-42.
考点梳理
考点
分析
点评
有理数的混合运算.
(1)(5)分类计算;
(2)先化简,再分类计算;
(3)利用乘法分配律简算;
(4)先判定符号,再按运算顺序计算;
(6)先算乘方,再算乘除,最后算加减.
此题考查有理数的混合运算,注意运算顺序与计算结果的符号,根据数字特点灵活选择合适的运算定律简算.
找相似题
计算:
(1)
(-2)÷[(-
1
2
)
2
×(
1
2
)
3
]×|-
25
4
|-(-5)
;
(2)-(-1)
2005
+4÷(-2)-|-1
2
|.
计算下列各式的值:
(1)
0.25×(-2
)
3
-[4÷(-
2
3
)
2
+1]+(-1
)
2008
;
(2)(
7
9
-
5
6
+
3
4
-
7
18
)×(-36).
计算:
-
1
4
-(
7
3
-
11
17
-
14
15
)×(-五五)÷(-1
)
7五五9
计算:
①
(
1
6
-
1
8
+
1
12
)÷(-
1
24
)
;
②-2
2
-(-2)
2
+(-3)
2
×(-
2
3
)-4
2
÷|-4|.
①计算:(+12)+(-23)-(-33)
②计算:
-
2
2
-16÷(-4)×(-
3
4
)