I have a question with solution and want to understand how we get the range given in the solution ?

Question

If L={a,b,c,d} and M={3,4} then find two binary relations of L*M

SolutionL*M={(a,3),(a,4),(b,3),(b,4),(c,3),(c,4),(d,3),(d, 4)}

Two binary relations of L*M are as follows:

R1={(a,3),(b,4),(c,3)}

R2={(a,4),(b,3),(c,4)}