In: Statistics and Probability
4.Consider events A and B, neither of which are impossible events. Prove the following
statements.
A)? ? ? = 1 − ?(?|?)
B)If ? ? ? ? = ? ? ∩ ? , then A and B must be independent events.
Question 4
Two events are A and B, neither of which are impossible events.
Question (A)
We have to prove
Now, we see
By definition of conditional probability,
Hence Proved.
Question (B)
If A and B are independent events, it means that the occurrence of A is independent of the occurrence of B.
In probability terms, it means
Now, it is given
By definition of conditional probability, this becomes
Hence proved, A and B must be independent.