Find two sets a and b such that a ∈ b and a ⊆ b.

Solution:

Let us consider set a ={} and set b ={ {},{1,2} }

Clearly, a belongs to set b as we know the empty set is a subset of every set.

So we can say a ∈ b.

The definition of the subset is that every element of set A should be contained in set B.

Therefore, a ⊆ b.

Find two sets a and b such that a ∈ b and a ⊆ b.

Summary:

The two sets a and b such that a ∈ b and a ⊆ b are {} and { {},{1} } respectively.