suppose an experiment has only two outcomes, e1 and e2

[mark]

I'm totally lost on this problem

Suppose an experiment has only two outcomes, e1 and e2, where P(e1) = p and p(e2) = p^2. what is p?

 

[pka]

Clearly in this space \(\displaystyle p + p^2 =1\), can you solve for p?

 

[mark]

did you add them because sigma p(x) = 1

 

[pka]

did you add them because sigma p(x) = 1

No. Sigma have has nothing to do with it.
You were given that there are exactly two elementary events (outcomes).
Therefore, the sum of the probabilities must equal 1.

 

[tkhunny]

did you add them because sigma p(x) = 1

I'm very puzzled by this question.

What does that sigma thing mean?

In this case, sigma(p(x)) = p + p^2 = 1.

 

[pka]

Hi TKH, I just realized that by sigma he meant 'SUM'.

 

[Denis]

“A mathematician is a blind man in a dark room looking for a black hat which he forgot he's wearing!”