Question

A = {a, b, c, d}

B = {c, d, e, f, g, h}

LaTeX: A\cup BA∪B is the set of all elements that belong to A or B.

When given this information Johnny stated that union of A and B is {a, b, e, f, g, h}.

POST (by Thursday): Is Johnny correct? If not, correct his answer. Either way give a every day example to justify your answer. After posting your response, please REPLY to the responses of your group members explaining whyyou agree or disagree with their response, or asking clarifying questions.

Answer 1

Johnny is wrong.

`A \cup B = \left\{a,b,c,d,e,f,g,h\right\}`

Explanation:

Johnny is wrong.

A better definition would be:
`A \cup B` is the set of all elements that belong to at least one A or B.

So, the elements that belong to both A and B, like c and d in this exercise, also belong to
`A \cup B`.

So:

`A \cup B=\left\{a,b,c,d,e,f,g,h\right\}`