Show that for any three events ?A, B, ?and ?C ?with P(C) > 0, P(A ?B|C) = P(A|C) + P(B|C) – P(A?B|C).

Answer : Step 1 : We use formula for conditional prob and a few set operations. P(A U B|C) = P[(AUB) C] /P(C) Now to make following this easier to read and write, I will work on the numerator only. Everything is over P(C) and I'll put...