Functions Question 408
Question: Let $ X={1,2,3,4,5} $ and $ Y={1,3,5,7,9}, $ which of the following is not relation form X to Y?
Options:
A) $ R_1={(x,y):y=x+2,x\in X,y\in Y} $
B) $ R_2={(1,1),(2,1),(3,3),(4,3),(5,5)} $
C) $ R_3={(1,1),(1,3),(3,5),(3,7),(5,7)} $
D) $ R_4={(1,3),(2,5),(2,4),(7,9)} $
Show Answer
Answer:
Correct Answer: D
Solution:
[d] $ R_1 $ is a relation from X to Y because $ R_1\subseteq X\times Y. $ $ R_2 $ is a relation form X to Y because $ R_2\subseteq X\times Y. $ $ R_3 $ is a relation from X to Y because $ R_3\subseteq X\times Y. $ $ R_4 $ is not a relation form X to Y because (2, 4), (7, 9) $ \notin X\times Y. $
BETA
