已知函数f(x)=2^(x-1)(1<=x<=3),求函数f=[f^(-1)(x)]^2+f^(-1)(x^2)的值域

来源:百度知道 编辑:UC知道 时间:2024/06/14 15:38:40
我要过程

f(x)=2^(x-1)(1<=x<=3),其定义域是[1,3],易求得值域是[1,4]
所以,可求得f^-1(x)=log2(x)+1,(1<=x<=4),(注:以2为底x的对数)
所以,F(x)=[f^(-1)(x)]^2+f^(-1)(x^2)
=[log2(x)+1]^2+log2(x^2)+1
=...
=[log2(x)+2]^2-2
1<=x<=4 ==> 0<=log2(x)<=2 ==> 2<=F(x)<=14
所以,所求的值域是[2,14]