- #1
dhillon
- 14
- 0
set theory question please help it urgent, thank you
1. 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
2. Homework Equations
X \ Y sets of elements in X but not Y. Y doesn't have to be a subset of X however if it is then X \ Y is the compliment of Y in X
3. The Attempt at a Solution
this is how i did it however i don't 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 don't have to be in set A or B , please see the attatched file for the diagrams , I am 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 therefore 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
Attached Files
Homework Statement
1. 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
2. Homework Equations
X \ Y sets of elements in X but not Y. Y doesn't have to be a subset of X however if it is then X \ Y is the compliment of Y in X
3. The Attempt at a Solution
this is how i did it however i don't 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 don't have to be in set A or B , please see the attatched file for the diagrams , I am 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 therefore 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
Attached Files