问题 解答题
已知x2-5x-2014=0,求代数式
(x-2)3-(x-1)2+1
x2-4x+4
÷
2x
2x2-4x
的值.
答案

∵x2-5x-2014=0,

∴x2-5x=2014,

∴原式=

(x-2)3-(x-1)2+1
(x-2)2
×
2x(x-2)
2x
=
(x-2)3-(x-1)2+1
x-2

=(x-2)2-

(x-1)2
x-2
+
1
x-2

=(x-2)2-

(x-1)2-1
x-2

=(x-2)2-

x(x-2)
x-2

=(x-2)2-x

=x2-5x+4

=2014+4

=2018;

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