Question

Let A = {circle, square} and let B = {3, 4, 5}. Find A X B.

{circle, square, 3, 4, 5}

{ }

{3, 4, 5}

{(circle, 3), (circle, 4), (circle, 5), (square, 3), (square, 4), (square, 5)}

Question 21 (Multiple Choice Worth 1 points)

[3.06]

If f(x) = x^2 - 1, find f(3).

5

2

8

-2

Answer 1

@AccessDenied @baldymcgee6

Answer 2

1) A x B means the set of all ordered pairs whose first entry is an eement of A and second is an element of B.
So, you'll have a set looking something like \(\{(a_1, b_2), \ (a_2, b_2)\}\) etc.

Answer 3

f(x) = x^2 - 1, find f(3)
f(3) = (3)^2 -1
f(3) = 9-1
f(3) = 8

Answer 4

for the first one is it A?

Answer 5

No, A) would simply be the union of the sets. This is represented as "A u B."
A x B will have ordered pairs as elements of the set, rather than single items from each set.

Answer 6

it has to be B or C right?

Answer 7

It would be D):
{(circle, 3), (circle, 4), (circle, 5), (square, 3), (square, 4), (square, 5)}

You can see the ordered pairs: (circle, 3), (circle, 4), etc. consist of one element from A first, and then one element from B second.

Basically, A x B is like the set of all combinations of elements from A and B. Would that make sense?