已知f(x)=x^2-1,g(x)=x-1(x小于0)或2-x(x大于0),求f[g(x)]与[f(x)]

问题描述:

已知f(x)=x^2-1,g(x)=x-1(x小于0)或2-x(x大于0),求f[g(x)]与[f(x)]

f[g(x)]=(x-1)^2-1=x^2-2x x0
g[f(x)]=x^2-1-1=x^2-2 (x^2-10)