Check if a relation on a set is a function
102592
Arbitrary Set A a Function??
95373
Additive set function on a semiring of sets
63276
Is an arbitrary union of a chain of countable sets countable?
111324
Finding number of relations on a set with 3 elements
146055
Proving a set of functions is uncountable
29232
Find total number of relations that are equivalence as well as partial order set
87830
Relating the union of the power set of a set to the set itself
55924
How many distinct functions can be defined from set A to B?
14994
Showing a function $f$ cannot be surjective
16225
Set-theoretical definition of function evaluation
22132
How to Map a subset of list elements to a function?
150857
Equivalence relations on S given no relation?
78300
Showing a set is closed other than giving a counterexample?
137921
Reflexivity, Transitivity, Symmertry of the square of an relation
89127
How do I prove if a set of operations is complete?
69426
Checking if the roots of a function are real
80209
If $X,Y$ are equivalence relations, so is $X \times Y$