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#1 2015-05-12 14:49:21
- mrpace
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- Registered: 2012-08-16
- Posts: 88
Which of the following are subrings of C?
Z[√7] = {a+b√7|a.b ∈ Z}
2Z+iZ = {2a+bi|a,b ∈ Z}
Where C is the complex plane, Z is the set of real integers.
Any ideas? Thanks.
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#2 2015-05-12 19:11:08
- Olinguito
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- Registered: 2014-08-12
- Posts: 649
Re: Which of the following are subrings of C?
The first one.
The second one is not even a ring – it's not closed under multiplication.
Bassaricyon neblina
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