(Q8). Let A = {a, e, i, o, u} and B = {a, i, u}. Show that A ∪ B = A.

We have A ∪ B = {a, e, i, o, u} ∪ {a, i, u}

= {, , , , , , , }

= {, , , , }

= .

This example illustrates that union of sets A and its subset B is the set A itself.

i.e, if B ⊂ A, then A ∪ B = .