Question

If $n\left(A\right)=5$ and $n\left(B\right)=7,$ then the number of relations on $A\times B$ is :

• A. $2^{35}$
• B. $2^{49}$
• C. $2^{25}$
• D. $2^{70}$
• E. $2^{35\times 35}$

Answer 1

Answer: (A)

$2^{35}$

Given, $n\left(A\right)=5$ and $n\left(B\right)=7$
Therefore, number of relations on $A\times B=2^{\left[n\right(A)\times n(B\left)\right]}$
$=2^{(5\times 7)}=2^{\left(35\right)}$