Let . Prove is an abelian group under multiplication. This makes sense since the units are group under multiplication. is the identity. How do I find the inverse?
Last edited by dwsmith; Aug 27th 2011 at 03:14 PM.
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Originally Posted by dwsmith Let . Prove is an abelian group under multiplication. is the identity. How do I find the inverse? Here is a hint: is a root of unity. is its inverse.
Originally Posted by Plato Here is a hint: is a root of unity. is its inverse. So the inverse is
For associative and commutative, that is trivial true since is a field, correct?
Originally Posted by dwsmith For associative and commutative, that is trivial true since is a field, correct? Well it is a field after all!