- #1

Math Amateur

Gold Member

MHB

- 3,998

- 48

I need help in order to fully understand the implications of Axler's definition of a $\sigma$-algebra ... ...

The relevant text reads as follows:

... BUT ... which of the three bullet points of the definition of a $\sigma$-algebra is violated by the set of all subsets of $\mathbb{R}$ ... and how/why is it violated ...

Help will be much appreciated ...

Peter