Question

Q.Which of the following are examples of the null set

(i) Set of odd natural numbers divisible by 2

(ii) Set of even prime numbers

(iii) {x: x is a natural numbers, x < 5 and x > 7}

(iv) {y: y is a point common to any two parallel lines}​

Answer 1

Answer:

(i) There is no odd natural number divisible by 2. Therefore, given set is an empty set / nullset. (ii) 2 is the even prime number. ∴ Given set = {2} ≠φ (iii) There is no natural number x, which is simultaneously less than 5 and greater than 7. So, given set is null set. (iv) We know that two parallel lines have no common point and hence the given set is null set.