已知函数f(x)=4x+3,g(x)=x2,求f[f(x)],f[g(x)],g[f(x)],g[g(x)]

问题描述:

已知函数f(x)=4x+3,g(x)=x2,求f[f(x)],f[g(x)],g[f(x)],g[g(x)]

f[f(x)]=4(4x+3)+3=16x+15
f[g(x)]=4(x²)+3=4x²+3
g[f(x)]=(4x+3)²=16x²+24x+9
g[g(x)]=(x²)²=x的四次方