Compute the G.C.D of two Gaussian Integers

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DeldotB
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Homework Statement


Hello all I apologize for the triviality of this:
Im new to this stuff (its easy but unfamiliar) I was wondering if someone could verify this:

Find the G.C.D of [itex]a= 14+2i[/itex] and [itex]b=21+26i[/itex].

[itex]a,b \in \mathbb{Z} [ i ][/itex] - Gaussian Integers

Homework Equations



None

The Attempt at a Solution



Well, is it true that any common divisor must also divide the G.C.D of the norm's of [itex]a[/itex]and[itex]b[/itex]?

If so then, [itex]norm(14+2i)=200[/itex]
[itex]norm(21+26i)=1117[/itex]

Well, since 1117 and 200 are co-prime, their greatest common divisor is one. Thus,

Thus the G.C.D of a,b is a unit (1,-1,i,-i) in the ring.

Thanks
 
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Everything that divides (a+bi) also divides (a+bi)(a-bi), sure.
DeldotB said:
Well, since 1117 and 200 are co-prime
In the integers. You'll have to show that this is true for Gaussian integer factors as well.