题目内容
计算:
+
+
+
+
+
+
+
=
.
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 8 |
| 1 |
| 31 |
| 1 |
| 62 |
| 1 |
| 124 |
| 1 |
| 248 |
| 1 |
| 496 |
| 15 |
| 16 |
| 15 |
| 16 |
分析:每相邻的两个分数拆项后,都有相同的数,故把每个分数拆为分数相减的形式:
=1-
;
=
-
;
=
-
…然后相加.
| 1 |
| 2 |
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 8 |
| 1 |
| 4 |
| 1 |
| 8 |
解答:解:原式=(1-
)+(
-
)+(
-
)+
+(
-
)+(
-
)+(
-
)+(
-
),
=1-
+
+
-
,
=
+
×(2-
)=
+
×
,
=
+
=
.
故答案为:
.
| 1 |
| 2 |
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 4 |
| 1 |
| 8 |
| 1 |
| 31 |
| 1 |
| 31 |
| 1 |
| 62 |
| 1 |
| 62 |
| 1 |
| 124 |
| 1 |
| 124 |
| 1 |
| 248 |
| 1 |
| 248 |
| 1 |
| 496 |
=1-
| 1 |
| 8 |
| 1 |
| 31 |
| 1 |
| 31 |
| 1 |
| 496 |
=
| 7 |
| 8 |
| 1 |
| 31 |
| 1 |
| 16 |
| 7 |
| 8 |
| 1 |
| 31 |
| 31 |
| 16 |
=
| 7 |
| 8 |
| 1 |
| 16 |
| 15 |
| 16 |
故答案为:
| 15 |
| 16 |
点评:此题考查了学生对分数的拆项的掌握情况,以及简算的能力.
练习册系列答案
相关题目