- #1

dhillon

- 14

- 0

**urgent help needed please, thanks**

## Homework Statement

Let A, B and C be any sets inside our universal set U. Decide whether each of the following statements is true or false. Justify your answers by giving a proof or a counterexample as appropriate.

a) A⊆B if and only if B'⊆A'

b) If A∩C ⊆ B∩C then A⊆B

## Homework Equations

X \ Y sets of elements in X but not Y. Y doesnt have to be a subset of X however if it is then X \ Y is the compliment of Y in X

## The Attempt at a Solution

this is how i did it however i dont think its right hence i need your help thanks

a) with these 2 venn diagrams it shows that this statement is false as the elements dont have to be in set A or B , please see the attatched file for the diagrams , im not sure please help thank you

b) With this venn diagram i think it shows the statement is true, this is as the set A has the the same elements that are also in set B therfore the statement is true. please help me out on this , see the attached document (i named the doc 2A for the first part n 2B for the second) thank you, please help