Question

Let $A = \\{a_1, a_2\\}$ and $B = \\{b_1, b_2\\}$, then the number of relations from $A$ to $B$ is

• A. $4$
• B. $8$
• C. $16$
• D. $2$

Answer 1

Answer: (C)

$16$

Answer 2

$n\left(A\right) = 2, n\left(B\right) = 2$ $\Rightarrow n\left(A \times B\right) = 4$ $\therefore$ Number of relations $=2^{n\left(A \times B\right)}$ $=2^4=16$