Question

Let `A = {1, 2, 3, 4}, B = {1, 5, 9, 11 , 15 , 16}`and`f = {(1, 5), (2, 9), (3, 1), (4, 5), (2, 11)}`. Are the following true?(i) f is a relation from A to B(ii) f is a function from A to B.Justify y

Answer 1

Correct Answer - (i) Yes (ii) No
(i) Since `fsubXxxY`, so f is a relation from X to Y.
(ii) Dom (f)=X and range `(f)={1,5,9,11}subY`.
But, two different ordered pairs namley (2,9) and (2,11) have the same first coordinate. So f is not a function.