Ex 2.1, 8 - Chapter 2 Class 11 Relations and Functions

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Ex 2.1, 8 Let A = {1, 2} and B = {3, 4}. Write A × B. How many subsets will A × B have? List them. A = {"1, 2" } & B = {"3, 4" } A × B = {"(1, 3), (1, 4), (2, 3), (2, 4)" } No of elements of A × B = n = 4 Number of subsets of A × B = 2n = 24 = 2 × 2 × 2 × 2 = 16 Therefore, the set A × B has 24 = 16 subsets. Finding Subsets of A × B A × B = {"(1, 3), (1, 4), (2, 3), (2, 4)" } One element {"(1, 3)" }, {"(1, 4)" }, {"(2, 3)" }, {"(2, 4)" }, Two elements {"(1, 3),(1, 4)" }, {"(1, 3), (2, 3)" }, {"(1, 3), (2, 4)" }, {"(1, 4), (2, 3)" }, {"(1, 4), (2, 4)" }, {"(2, 3), (2, 4)" }, Three elements {"(1, 3), (1, 4), (2, 3)" }, {"(1, 3), (1, 4), (2, 4)" }, {"(1, 3), (2, 3), (2, 4)" }, {"(1, 4), (2, 3), (2, 4)" }, Four elements {"(1, 3), (1, 4), (2, 3), (2, 4)" }, No element ϕ