问题
选择题
已知f(x)=
|
答案
∵f(x)=1+x2 1-x2
∴f(-x)=
=1+(-x)2 1-(-x)2
,f(-x)=f(x),即满足A选项1+x2 1-x2
f(
) =1 x
=1+(
)21 x 1-(
)21 x
,f(x2+1 x2-1
)=-f(x),即满足B选项,不满足C选项1 x
f(-
) =1 x
=1+(-
)21 x 1-(-
)21 x
,f(-x2+1 x2-1
)=-f(x),即满足D选项1 x
C不满足
∴故选C