简单函数!(急!!)

来源:百度知道 编辑:UC知道 时间:2024/06/02 08:27:48
我要过程!!

证明:
(1)
f(x)=(1+x^2)|(1-x^2)
f(-x)=(1+(-x)^2)/(1-(-x)^2)
=(1+x^2)|(1-x^2)
∴f(-x)=f(x)

(2)
f(1/x)=[1+x^(-2)]/[(1-1/x)(1+1/x)]
=[1+x^(-2)]/[(x^2-1)/x^2]
=[(x^2+1)/x^2]/[(x^2-1)/x^2]
=(x^2+1)/(x^2-1)
=-(1+x^2)/(1-x^2)
=-f(x)

把-x带入f(x),化简即可得证;
把1/x带入f(x),化简即可。

f(-x)=1+(-x)^2/1-(-x)^2=1+x^2/1-x^2
f(1/x)=(1=1/x^2)/(1-1/x^2)=(x^2+1)/(x^2-1)=-f(x)

(1)
f(x)=(1+x^2)|(1-x^2)
f(-x)=(1+(-x)^2)/(1-(-x)^2)
=(1+x^2)|(1-x^2)
∴f(-x)=f(x)

(2)
f(1/x)=[1+x^(-2)]/[(1-1/x)(1+1/x)]
=[1+x^(-2)]/[(x^2-1)/x^2]
=[(x^2+1)/x^2]/[(x^2-1)/x^2]
=(x^2+1)/(x^2-1)
=-(1+x^2)/(1-x^2)
=-f(x)