# Is this an equivalent formula for P(A or B or C) ?

1. Mar 8, 2007

### opticaltempest

I was trying to derive a formula to find $$P(A \cup B \cup C)$$.

I came up with the following:

Is that correct?

2. Mar 8, 2007

### IMDerek

Yes it's correct

3. Mar 8, 2007