Which of the following are pairs of equal sets?

E = {x : x ϵ Z, x2 ≤ 4} and F = {x : x ϵ Z, x2 = 4}.


Equal Sets = Two sets A and B are said to be equal if they have exactly the same elements & we write A = B


We have,


E = {x : x ϵ Z, x2 ≤ 4}


Here, x Z and x2 ≤ 4


If x = -2, then x2 = (-2)2 = 4 = 4


If x = -1, then x2 = (-1)2 = 1 < 4


If x = 0, then x2 = (0)2 = 0 < 4


If x = 1, then x2 = (1)2 = 1 < 4


If x = 2, then x2 = (2)2 = 4 = 4


So,


E = {-2, -1, 0, 1, 2}


and F = {x : x ϵ Z, x2 = 4}


Here, x Z and x2 = 4


If x = -2, then x2 = (-2)2 = 4 = 4


If x = 2, then x2 = (2)2 = 4 = 4


So, F = {-2, 2}


E ≠ F because the elements in the both the sets are not equal.


1