Mathematics

Problem

Let

A=\{1,2,3\}

and

B=\{4,5,6\}

. The relation

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

is a subset of

A\times B

. Find the domain of

R

. a) \{4,5,6\} b) \{1,2\} c) \{1,2,3\} d) \{4,5\}