1. Chapter 1 Class 11 Sets
2. Serial order wise

Transcript

Ex 1.1,5 List all the elements of the following sets: (i) A = {x: x is an odd natural number} Natural numbers = 1,2,3,4,5,6,7,8,9,10,…. Odd Natural numbers = 1,3,5,7,8,11,…. So, the elements of this set are 1, 3, 5, 7, 9, 11,... Hence, A = { 1,3,5,7,9,……} Ex 1.1,5 List all the elements of the following sets: (ii) B = {x: x is an integer, −﷐1﷮2﷯ < x < ﷐9﷮2﷯} Given −﷐1﷮2﷯ < x < ﷐9﷮2﷯ i.e. -0.5 < x < 4.5 Integers = ......-4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, …. Elements of the given set are 0,1,2,3,4 Thus, B = {0,1,2,3,4} Ex 1.1,5 List all the elements of the following sets: (iii) B = {x: x is an integer, x2 ≤ 4} Integers = ......-4,-3,-2,-1,0,1,2,3,4,5,6,7,8,9,10…. (0)2 = 0 (1)2 = 1 (2)2 = 4 (3)2 = 9 (-1)2 = 1 (-2)2 = 4 (-3)2 = 9 The elements are -2,-1,0,1,2, Ex 1.1,5 List all the elements of the following sets: (iv) D = {x: x is a letter in the word “LOYAL”} In the word “LOYAL” the letter L is repeated. So, the elements in the set are L, O, Y, A. D = {L,O,Y,A} Ex 1.1,5 List all the elements of the following sets: (v) E = {x: x is a month of a year not having 31 days} We need months having 30 days as well as 28 days(February) Hence, the elements are February, April, June, September, November. E = {February, April, June, September, November} Ex 1.1,5 List all the elements of the following sets: (vi) F = {x: x is a consonant in the English alphabet which proceeds k}. Vowels are a, e, i, o, u Thus, the consonants before k are b, c, d, f, g, h, j are consonants So, the elements of the set are b, c, d, f, g, h, j F = {b, c, d, f, g, h, j}

Chapter 1 Class 11 Sets
Serial order wise