题目内容
当x=
时,则式子(4x3-2012x-2009)2009的值为 .
1+
| ||
| 2 |
考点:二次根式的化简求值
专题:
分析:首先把x的值代入4x3-2012x-2009求得代数式的值,然后所求的代数式的值即可求解.
解答:解:4x3-2012x-2009
=
(2x)3-2012×
-2009
=
(1+
)3-1006(1+
)-2009
=
【(2010+2
)(1+
)】-1006(1+
)-2009
=(1005+
)(1+
)-1006(1+
)-2009
=1006+2009+1006
-1006-1006
-2009
=0,
则(4x3-2012x-2009)2009=0.
故答案是:0.
=
| 1 |
| 2 |
1+
| ||
| 2 |
=
| 1 |
| 2 |
| 2009 |
| 2009 |
=
| 1 |
| 2 |
| 2009 |
| 2009 |
| 2009 |
=(1005+
| 2009 |
| 2009 |
| 2009 |
=1006+2009+1006
| 2009 |
| 2009 |
=0,
则(4x3-2012x-2009)2009=0.
故答案是:0.
点评:本题考查了二次根式的化简求值,正确理解乘法公式,求得4x3-2012x-2009的值是关键.
练习册系列答案
相关题目