题目内容
观察下列各式的计算结果
1-
=1-
=
=
×
1-
=1-
=
=
×
1-
=1-
=
=
×
1-
=1-
=
=
×
…
(1)用你发现的规律填写下列式子的结果:
1-
=
×
1-
=
×
(2)用你发现的规律计算:
(1-
)×(1-
)×(1-
)×…×(1-
)×(1-
).
1-
| 1 |
| 22 |
| 1 |
| 4 |
| 3 |
| 4 |
| 1 |
| 2 |
| 3 |
| 2 |
1-
| 1 |
| 32 |
| 1 |
| 9 |
| 8 |
| 9 |
| 2 |
| 3 |
| 4 |
| 3 |
1-
| 1 |
| 42 |
| 1 |
| 16 |
| 15 |
| 16 |
| 3 |
| 4 |
| 5 |
| 4 |
1-
| 1 |
| 52 |
| 1 |
| 25 |
| 24 |
| 25 |
| 4 |
| 5 |
| 6 |
| 5 |
…
(1)用你发现的规律填写下列式子的结果:
1-
| 1 |
| 62 |
| 5 |
| 6 |
| 5 |
| 6 |
| 7 |
| 6 |
| 7 |
| 6 |
1-
| 1 |
| 1002 |
| 99 |
| 100 |
| 99 |
| 100 |
| 101 |
| 100 |
| 101 |
| 100 |
(2)用你发现的规律计算:
(1-
| 1 |
| 22 |
| 1 |
| 32 |
| 1 |
| 42 |
| 1 |
| 20122 |
| 1 |
| 20132 |
分析:(1)根据发现的规律得出结果即可;
(2)根据发现的规律将所求式子变形,约分即可得到结果.
(2)根据发现的规律将所求式子变形,约分即可得到结果.
解答:解:(1)1-
=1-
=
=
×
,
1-
=1-
=
=
×
;
(2)根据题意得:原式=
×
×
×
×
×
×
×
×…×
×
=
.
故答案为:
;
;
.
| 1 |
| 62 |
| 1 |
| 36 |
| 35 |
| 36 |
| 5 |
| 6 |
| 7 |
| 6 |
1-
| 1 |
| 1002 |
| 1 |
| 10000 |
| 9999 |
| 10000 |
| 99 |
| 100 |
| 101 |
| 100 |
(2)根据题意得:原式=
| 1 |
| 2 |
| 3 |
| 2 |
| 2 |
| 3 |
| 4 |
| 3 |
| 3 |
| 4 |
| 5 |
| 4 |
| 4 |
| 5 |
| 6 |
| 5 |
| 2012 |
| 2013 |
| 2014 |
| 2013 |
=
| 1007 |
| 2013 |
故答案为:
| 5 |
| 6 |
| 7 |
| 6 |
| 99 |
| 100 |
| 101 |
| 100 |
点评:此题考查了有理数的混合运算,熟练掌握运算法则是解本题的关键.
练习册系列答案
相关题目