Question

Let X={1.2.3.4), verify which of the following relations are functions from X to X​

Answer 1

={(x,y):y=2+x,x∈X,y∈Y}

x=1→y=1+2=3

x=2→y=2+2=4

x=3→y=3+2=5

x=4→y=4+2=6

x=5→y=5+2=7

R={(1,3),(2,4),(3,5),(4,6),(5,7)}

Here in(4,6) ,6 does not belong to either XorY

So R

1

is not a relation between X and Y

In R

4

, since it contains an element (7,9) which relates set Y to set Y, while rest elements relate set X to Y.

∴R

4

is not a relation between X and Y