问题 填空题
x
x2+x+1
=a(a≠0且a≠
1
2
)
,则
x2
x4+x2+1
的值为______.
答案

x
x2+x+1
=a(a≠0且a≠
1
2
)⇒
x2+x+1
x
=
1
a
⇒x+
1
x
=
1
a
-1

x2
x4+x2+1
=
1
x2+1+
1
x2
=
1
(x+
1
x
)
2
-1

=

1
(
1
a
-1)
2
-1 

=

1
1
a2
-
2
a

=

a2
1-2a

故答案为:

a2
1-2a

填空题
单项选择题