Question

Write the domain of the relation R defined on the set Z of integers as follows:
(a, b) ∈ R ⇔ a² + b² = 25

Answer 1

Domain of R is the set of values satisfying the relation R.
As a should be an integer, we get the given values of a:

$$\begin{gathered} 0,\pm 3,\pm 4,\pm 5 \\ \mathrm{Thus}, \\ \mathrm{Domain}\mathrm{of}R=\left\{0,\pm 3,\pm 4,\pm 5\right\} \end{gathered}$$