Question

f(x) = 4x+3 . show that f is invertible and find its inverse

Answer 1

let F(x)=4x+3=y
x=y-3/4=g(y)
gof(x)=g{f(x)}=g(4x+3)=4x+3-3/4=4x/4x=x
fog(y)=f{g(y)}=f(y-3/4)=4×(y-3/4)+3=y-3+3=y because fog(y)=y and gof(x)=x so F(x) is invertible and inverse of f(x) is g(y)=y-3/4