Okay, this question. Hmm sounds familiar if the union of a and b is
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then the intersection of the complement of A and B is just the cresent in B which can be found from the fact that the intersection of A and B is just
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and then to find the intersection of the complement of A and B we do
Part b is like this If A and B are mutually exclusive what happens is that suppose A and B are separate circles that do not touch what we have here is the complement of A is everything outside of A and the intersection of the complement of A and B is just B giving us