Question

If A is the set of even natural numbers less than 8 and B is the set of prime numbers less than 7, then the number of relations from A to B is

• A. $2 ^ { 9 }$
• B. $9 ^ { 2 }$
• C. $3 ^ { 2 }$
• D. $2 ^ { 9 - 1 }$

Answer 1

Answer: (A)

$2 ^ { 9 }$

Answer 2

$B = \{ 2,3,5 \}$

∴ A × B contains $3 \times 3 = 9$ elements.

Hence, number of relations from A to B $= 2 ^ { 9 }$.