Q1 of 23 Page 41

Which of the following sets are equal?

(i) A = {x: x is a letter in the word FOLLOW}


(ii) B = {x: x is a letter in the word FLOW}


(iii) C = {x: x is a letter in the word WOLF}

We know that two sets A and B are equal if every element in A belongs to B and every element in B belongs to A.


⇒ Roster form of A = {F, O, L, W}


⇒ Roster form of B = {F, L, O, W}


⇒ Roster form of C = {W, O, L, F}


So, the elements of A, B and C are same.


∴ A, B and C are equal sets.


More from this chapter

All 23 →
6

If A = {3, 6, 9, 12, 15, 18, 21}; B = {4, 8, 12, 16, 20} C = {2, 4, 6,8, 10, 12, 14, 16}; D = {5, 10, 15, 20} find

(i) A – B (ii) A – C


(iii) A – D (iv) B – A


(v) C – A (vi) D – A


(vii) B – C (viii) B – D


(ix) C – B (x) D – B

 7

State whether each of the following statement is true or false. Justify you answers.

(i) {2, 3, 4, 5} and {3, 6} are disjoint sets.


(ii) {a, e, i, o, u} and {a, b, c, d} are disjoint sets.


(iii) {2, 6, 10, 14} and {3, 7, 11, 15} are disjoint sets.


(iv) {2, 6, 10} and {3, 7, 11} are disjoint sets.

 2

Consider the following the following sets and fill up the blank in the statement given below with = or ≠ so as to make the statement true.

A = {1, 2, 3};


B = {The first three natural numbers};


C = {a, b, c, d};


D = {d, c, a, b}


E = {a, e, i, o, u};


F = {set of vowels in English Alphabet}


(i) A ….. B (ii) A ….. E


(iii) C ….. D (iv) D ….. F


(v) F ….. A (vi) D ….. E


(vii) F ….. B

 3

In each of the following, state whether A = B or not.

(i) A = {a, b, c, d}


B = {d, c, a, b}


(ii) A = {4, 8, 12, 16}


B = {8, 4, 16, 18}


(iii) A = {2, 4, 6, 8, 10}


B = {x: x is a positive even integer and x < 10}


(iv)A = {x: x is a multiple of 10}


B = {10, 15, 20, 25, 30, ….}