Step-by-step explanation:

It is given in the question that, A and B are two sets such that,

A ⊂ B

Let us take, A = {a, b}

And, B = {a, b, c} we have:

A ∪ B = {a,b,c} = B

JAI SHREE KRISHNA

Answer:

A U B = B

Step-by-step explanation:

let A={a,b,c}

and B={a,b,c,d}

here A C B

A U B = {a,b,c} U {a,b,c,d}

A U B = {a,b,c,d}

A U B = B