Which of the relations is not a function?
one-one
many one
domain = codomain
one many
For a relation to be a function one element of the domain must not be connected with more than one elements of the co-domain. Hence the answer.
Let A = {1, 2, 3, 4, 5, 6}. Define a relation on set A by R = {(X, Y): y = x +1}
(i) Depict this relation using an arrow diagram.
(ii) Write down the domain, codomain and range of R.
How many trivial relations can be formed on a set which has 64 elements?