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# Group help watch

1. Let be a field (with ) and define:

I'm trying to prove that is a group with multiplication. This identity shows closure:

Can someone help with finding the inverse?
2. Hold on, you have two binary operations (addition, multiplication) on F? Is F meant to be a field (or a ring)? "Sum of squares" doesn't really make much sense in the context of a group.
3. (Original post by nuodai)
Hold on, you have two binary operations (addition, multiplication) on F? Is F meant to be a field (or a ring)? "Sum of squares" doesn't really make much sense in the context of a group.
Typo sorry. (Edited).
4. (Original post by 0-))
Typo sorry. (Edited).
Ah alright. Well you can write as . How else can this be written?
5. (Original post by nuodai)
Ah alright. Well you can write as . How else can this be written?
As the sum of two squares!
6. (Original post by 0-))
As the sum of two squares!
Correct

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