Question

Given the following definitions: U = {1, 2, 3, 4, 5, 6, 7} A = {1, 2, 4, 5} B = {1, 3, 5, 7} How many elements are in A' ∩ B' ? Your Answer:

Answer 1

1 element

Explanation:

A' means not A and B' means not B

∩ means both

so now we have how many elements are not in A and not in B

A has 1,2,4,5 so not A will be 3,6,7

B has 1,3,5,7 so not B will be 2,4,6

now we look at what not A and not B have together and that is 1 element {6}

Answer 2

`A'=\{3,6,7\}\\B'=\{2,4,6\}\\A'\cap B'=\{6\}`

Therefore,
`n(A'\cap B')=1`.