What is Image of f(x)?
Divide the domain R to 2 intervals D1 and D2 to get two inverse functions in these intervals. Calculate these functions.
I'm afraid Nacho is incorrect. He may be thinking of the "domain" rather than the "range" or image. Complete the square on that quadratic: . Now it should be clear that f(x) is never larger than 6. And that should make it clear how to solve for x to find the two "inverse" functions.
Ohh.. now it's a little bit clearer...
-How can I prove that f:R-->(inf,6] is not inverse?
-What are the two intervals that I must take to prove that f is inverse.
I mean: f_1-->(inf,6] and f_2-->(inf,6], which intervals should I take (D_1, D_2)?
And thank you a lot!