Question

State, if the following pair of a set is equal or not :

A = {2, 4, 6, 8} and B = {2n : n ∈ N and n < 5}

Answer 1

A = {2, 4, 6, 8} and 

B = {2n : n ∈ N and n < 5}

When n = 1, 2n = 2 x 1= 2

When n = 2, 2n = 2 x 2= 4

When n = 3, 2n = 2 x 3= 6

When n = 4, 2n = 2 x 4= 8

∴ B = {2, 4, 6, 8}

Now we see that elements of sets A and B are the same (identical)

∴  Sets A and B are equal.