Week5 - Relations #

This week we talk about relations and their properties. Then we look at equivalence relations and partial order relations.

Resources #

Also look at discmath.ch for more exercises, worked examples and explanations!

Exercise 3) was hard. Don’t worry if you couldn’t solve it.
Read the task description!! If it says “every step needs to be justified”, then every step needs to be justified.
You cannot just assume things (even if they are correct) without proving them.
Don’t manipulate formulas with 0, 1, $\top$, $\bot$. Write something like “since we know that … is true we know that …”.
From now on you most likely won’t need truth tables anymore. If you take more than one page or need to argue a lot and in weird ways then there most likely is a more “clean” way to do it.
It is not enough if you understand your proof, the person who reads it needs to understand it.
Don’t make things more complicated than they need to be. If you saw a method in class, try to do it exactly like that first.

Do all of them! If you have to leave out one, then skip 5.5.