Question

If A = {positive integers} and B = {negative integers}, what is A ∩ B?

{ }

{…, −3, −2, −1, 1, 2, 3 …}

{1, 2, 3, 4 …}

{…−3, −2, −1}

Answer 1

What does the upside down U mean?

Answer 2

united

Answer 3

No. It means "intersection" or in other words:

Answer 4

Name the elements that the two sets share.

Answer 5

Find a number that is in set A and also in set B