Thread: Surjectivity of (x^3) +5

How can I prove the surjectivity of this function? I know I'm trying to prove that for all y in the range there exists an x in the domain such that , but I can't think how to go about proving it. Thanks.

Originally Posted by Greengoblin

How can I prove the surjectivity of this function?

Does exist fo every y?

Ah yes thanks. I was trying to show it's onto in order to show that it has an inverse, but I didn't think to try it the other way round.