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 |
| 32 |
| 1 |
| 9 |
| 8 |
| 9 |
| 2 |
| 3 |
| 4 |
| 3 |
1-
| 1 |
| 42 |
| 1 |
| 16 |
| 15 |
| 16 |
| 3 |
| 4 |
| 5 |
| 4 |
| 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 |
| 1 |
| 102 |
(2)用你发现的规律计算:
(1-
| 1 |
| 22 |
| 1 |
| 32 |
| 1 |
| 42 |
| 1 |
| 20132 |
| 1 |
| 20142 |
考点:有理数的混合运算
专题:规律型
分析:(1)根据平方差公式即可求解;
(2)先根据平方差公式变形,再约分计算即可求解.
(2)先根据平方差公式变形,再约分计算即可求解.
解答:解:(1)1-
=
×
;
1-
=
×
;
(2)(1-
)×(1-
)×(1-
)×…×(1-
)×(1-
)
=
×
×
×
×…×
×
=
×
=
.
故答案为:
,
;
,
.
| 1 |
| 62 |
| 5 |
| 6 |
| 7 |
| 6 |
1-
| 1 |
| 102 |
| 9 |
| 10 |
| 11 |
| 10 |
(2)(1-
| 1 |
| 22 |
| 1 |
| 32 |
| 1 |
| 42 |
| 1 |
| 20132 |
| 1 |
| 20142 |
=
| 1 |
| 2 |
| 3 |
| 2 |
| 2 |
| 3 |
| 4 |
| 3 |
| 2013 |
| 2014 |
| 2015 |
| 2014 |
=
| 1 |
| 2 |
| 2015 |
| 2014 |
=
| 2015 |
| 4028 |
故答案为:
| 5 |
| 6 |
| 7 |
| 6 |
| 9 |
| 10 |
| 11 |
| 10 |
点评:此题考查了有理数的混合运算,熟练掌握平方差公式是解本题的关键.
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