Question

What is the domain of the inverse f^-1(X)= (x^2)-4/5

Answer 1

the domain of the inverse of f(x) is the range of f(x)

if f^-1 (x) = x^2 - 4/5
the inverse of that is
x = y^2 - 4/5
5x = 5y^2 - 4
(5x+4)/5 = y^2
f(x) = y = ±√((5x+4)/5) <----- the range of that is any real number