题目内容

观察下列各式计算结果:
1-
1
22
=1-
1
4
=
3
4
=
1
2
×
3
2

1-
1
32
=1-
1
9
=
8
9
=
2
3
×
4
3

1-
1
42
=1-
1
16
=
15
16
=
3
4
×
5
4

1-
1
52
=1-
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
102
=
 
.1-
1
1002
=
 
.1-
1
20142
=
 

(2)用你发现的规律计算:
(1-
1
22
)×(1-
1
32
)×(1-
1
42
)×…×(1-
1
20132
)×(1-
1
20142
).
考点:规律型:数字的变化类
专题:
分析:(1)根据平方差公式分解因式进而求出即可;
(2)利用(1)中变化规律进而化简求出即可.
解答:解:(1)∵1-
1
22
=1-
1
4
=
3
4
=
1
2
×
3
2

1-
1
32
=1-
1
9
=
8
9
=
2
3
×
4
3

1-
1
42
=1-
1
16
=
15
16
=
3
4
×
5
4

1-
1
52
=1-
1
25
=
24
25
=
4
5
×
6
5

∴1-
1
102
=
9
10
×
11
10
.1-
1
1002
=
99
100
×
101
100
.1-
1
20142
=
2013
2014
×
2015
2014

故答案为:
9
10
×
11
10
99
100
×
101
100
2013
2014
×
2015
2014


(2)(1-
1
22
)×(1-
1
32
)×(1-
1
42
)×…×(1-
1
20132
)×(1-
1
20142

=
1
2
×
3
2
×
2
3
×
4
3
×
3
4
×
5
4
×
2012
2013
×
2014
2013
×
2013
2014
×
2015
2014

=
2015
4028
点评:此题主要考查了数字变化规律,根据平方差公式得出数字之间的变化规律是解题关键.
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