If R is a relation defined on the set Z of integers by the rule (x,y)ϵR⇔x2+y2−9, then write domain of R.
We have,
(x,y)ϵx2+y2=9
⇒y2−9−x2
⇒y−√9−x2
Putting x = -3, 0, 3, we get y=0,±3,0 respectively.
For all other values of x, we get y/ϵz.
∴ Domain (R) = {-3, 0, 3}