Week 1 - Monday

Difficult
In section 1.4, I still don't understand how property #8 works. I'm assuming this property applies when the events are not disjoint, or else property #3 would apply. When comparing this with Example (13), I come up with more questions. Why do we add some probabilities and subtract others? How can we be sure that this outcome will be less than or equal to 1? What happens when there are more than three events?
Reflective
I'm having a little trouble grasping the concept of F, a collection of subsets of omega, but I think it's analogous to the concept of a field F in linear algebra. When deciding whether or not A is an event, you must make sure A and its complement are in F. Although, if F is a collection of subsets of omega, how can omega be in F?