Which is the inverse of f(x)=(x-3)²?
a. f⁻¹(x)=x² / (3 x-1)²
b. f⁻¹(x)=± √x+3
c. f⁻¹(x)= 1 / (3 x-1)²
d. f⁻¹(x)=± √x-3