- #1
pamparana
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Hello,
Trying to go through Tom Apostle text on Calculus. There is an exercise about proving the associative law for sets:
So, (A U B) U C = A U (B U C)
So, if we assume x to be an element in set in left hand side, than we can say x belongs at least to either A, B or C which in turn means that x is also an element in set in right hand side and then we can say that the LHS and RHS are subsets of each other...
Is this a valid proof? I am never sure with these. It is really tricky to prove such ideas that we take for granted in every day life!
Anyway, I would be really grateful for any help you can give this old man.
/Luca
Trying to go through Tom Apostle text on Calculus. There is an exercise about proving the associative law for sets:
So, (A U B) U C = A U (B U C)
So, if we assume x to be an element in set in left hand side, than we can say x belongs at least to either A, B or C which in turn means that x is also an element in set in right hand side and then we can say that the LHS and RHS are subsets of each other...
Is this a valid proof? I am never sure with these. It is really tricky to prove such ideas that we take for granted in every day life!
Anyway, I would be really grateful for any help you can give this old man.
/Luca