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Question
If R = {(x, y) : x2 + y2 ≤ 4; x, y ∈ Z} is a relation on Z, write the domain of R.
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Solution
Domain of R is the set of values of x satisfying the relation R.
As x must be an integer, we get the given values of x:
0, ±1, ±2
Thus,
Domain of R = {0, ±1, ±2}
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