If the sets A and B are defined as A=(x,y):y=ex,x∈R;B={(x,y):y=x,x∈R}, then
B⊆A
A⊆B
A∩B=ϕ
A∪B=A
Since y = ex and y = x do not meet for any x∈R∴A∩B=ϕ.