设f (x)={2x+1(x≥0),x²+4(x

问题描述:

设f (x)={2x+1(x≥0),x²+4(x

题目是替换变量,就是把x变成x-1,或者x+1
由于f (x)={2x+1(x≥0),x²+4(x