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Maths HL Core - Bayes' Theorem

Hi There,
some of you may have noticed that in Formula Booklet in the same box as the Conditional Probability formula, which is P(A|B)=P(A union B)/ P(B) , there is Bayes' Theorem. It is a far more complicated formula for doing conditional probablility. Do you know if we are ever expected to use it in IB maths exams, and what makes it different from the usual conditional probability formula?
Cheers
Reply 1
I have never encountered a case in which I've needed to use Baye's Theorem in a past paper.
Original post by BananaPie
I have never encountered a case in which I've needed to use Baye's Theorem in a past paper.


Doesn't mean it's not going to come up this time though does it?
Reply 3
Usually the probability questions that IB asks are the standard problem based questions. For those you will have no problem solving them by drawing a simple tree diagram. However once in a while they will ask questions that does not involve any context, and so using a tree diagram may not be so straightforward. If the question gives information like p(A|B) then the equations could be useful. As to Bayes' theorem, just know that it's in the formula booklet, and if in case a strange question comes out in the exam (one that you find it difficult to solve using simple logic), then the formula might come in handy.

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