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rareDenise47
Decide whether or not the modulo system forms a group. {0, 1}; multiplication modulo 2
Before I start, what do you think, and why?
there are three parts to test, (i) associativity, (ii) existence of an identity, and (iii) every element has an inverse relative to the given operation
now, if you think the modulo system is not a group, which of the three parts (i) associativity, (ii) identity, or (iii) inverse will fail?