题目内容
用自己喜欢的方式计算
|
|
|
分析:(1)根据加法交换律进行简算;
(2)根据加法交换律和结合律进行简算;
(3)根据加法交换律和结合律进行简算.
(2)根据加法交换律和结合律进行简算;
(3)根据加法交换律和结合律进行简算.
解答:解:(1)
+
+
=
+
+
=1+
=1
;
(2)
+
+
+
=(
+
)+(
+
)
=
+1
=1
;
(3)
+
+
+
=(
+
)+(
+
)
=2+
=2
.
| 2 |
| 5 |
| 1 |
| 3 |
| 3 |
| 5 |
=
| 2 |
| 5 |
| 3 |
| 5 |
| 1 |
| 3 |
=1+
| 1 |
| 3 |
=1
| 1 |
| 3 |
(2)
| 1 |
| 4 |
| 1 |
| 3 |
| 1 |
| 4 |
| 2 |
| 3 |
=(
| 1 |
| 4 |
| 1 |
| 4 |
| 1 |
| 3 |
| 2 |
| 3 |
=
| 1 |
| 2 |
=1
| 1 |
| 2 |
(3)
| 9 |
| 7 |
| 1 |
| 8 |
| 3 |
| 8 |
| 5 |
| 7 |
=(
| 9 |
| 7 |
| 5 |
| 7 |
| 1 |
| 8 |
| 3 |
| 8 |
=2+
| 1 |
| 2 |
=2
| 1 |
| 2 |
点评:此题主要考查分数的四则混合运算的运算顺序和应用运算定律进行简便计算.
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