# Primes With Complex Factors

Ceri Davies ceri at submonkey.net
Sun May 11 20:50:42 BST 2008

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On Sun, May 11, 2008 at 08:42:27PM +0100, Lee Brotherston wrote:
> On Sun, May 11, 2008 at 08:12:07PM +0100, Frank Shute wrote:
> > Lee, I made your maths wrong:
>=20
> Ah yes, damn those -'s (not having the best day).  Like you say I'd
> like to see some other numbers
>=20
>=20
> > (1+i)(1-i)=3D2
> >=20
> > expanding LHS:
> >=20
> > 1 + i - i - (i)^2 =3D 2
> >=20
> > simplifying LHS:
> >=20
> > 1 - (i)^2 =3D 2
> >=20
> > since (i)^2 =3D -1:
> >=20
> > 1 - (-1) =3D 2
>=20
> I'm still not sure where this step came from though.  If i^2 =3D -1 then
> i will presumably be the square root of -1, and there are no square
> roots of negative figures, if memory serves.

Of course there are; that was generally AS or degree level stuff when I
was doing my degree though.  That's what "complex numbers" are.

Ceri
--=20
That must be wonderful!  I don't understand it at all.
-- Moliere

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