Question

Suppose a set A={January, February and August} and B={28, 15 and 30}. Write a relation R given by $R=(a,b)ϵA\times B,\text{where a is month and b has number of day}$.
Also find $R^{-1}$. Which ordered pair represent an Independence day?

Answer 1

Given sets are A={January, February and August} and B={28, 15 and 30}

$\therefore$ R= {(January, 28), (January, 15), (January, 30), (February, 28), (February, 15), (February, 30), (August, 28), (August, 15), (August, 30)}

and $R^{-1}$ = {(28, January), (15, January), (30, January), (28, February), (15, February), (30, February), (28, August), (15, August), (30, August)}

The ordered pair which represent independence day is (August, 15).