Question 1177280

Generally a constant function {{{y = C}}}, can {{{NEVER}}} be one-to-one since for different values of {{{x}}} we have the same value of {{{y}}}, namely {{{C}}}. 

Similarly, it can not be {{{onto}}} as other than {{{C}}} no element in co-domain will have pre-image in domain.

But yes there {{{might}}} be a case in which there is only {{{C}}} in co-domain then in this scenario we can say that function is {{{onto}}}.

Thus, in general a constant function can neither be onto nor one-one.