What is the meaning of an injective function?

the part of the graph of a non- injective function

Surjective Injective Bijective Functions

SOLVED: Using the precise definition of a function and a little logic, show that for every set Y there is exactly one function f from to Y When is injective? Surjective? Let X be a set. Show that there are either no functions from X to Ol' exactly one Such funetion, depending OH whether X = 0 Ol' X =0