Re: complex numbers


"N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@xxxxxxxxxx> wrote in message news:uLfre.7177$7s.91@xxxxxxxxxxxxx
> Dear jem:
>
> "jem" <xxx@xxxxxxx> wrote in message
> news:FVere.91014$sy6.84187@xxxxxxxxxxxxx
> > The TimeLord wrote:
> ...
> >> You can see that unless you keep straight just what
> >> the square root is defined to be,
> >
> > Sqrt() is defined to be a function so e.g. Sqrt(1) = 1,
> > not +-1, and of course i^2 = -1, not +-1.
>
> sqrt() may be defined by programming languages to be "the
> positive square root", allowing the programmer to assign whatever
> sign(s) the programmer chooses. But the result of the square
> root is bivalued

Well, point me to *one* single technical or engineering
publication or text in the world where they have an equation
where they mean anything other than 3 when they write sqrt(9),
and you are in business.
sqrt is the positive root of a positive number.

> (except for sqrt(0) ). sqrt(-1) is the
> conundrum, i^2 is the solution.

There is no such thing as sqrt(-1).
sqrt(-1) is for bad enceclopedias.

> And note that +/-i *is* a
> solution, and valid result.

Bot i and -i are things that give -1 when squared. You can
safely forget everything else.

Dirk Vdm


.

Relevant Pages

  • Re: complex numbers
    ... "Dirk Van de moortel" ... >> signthe programmer chooses. ... > sqrt is the positive root of a positive number. ... We have chosen the negative sign of the square root in equation ...
    (sci.physics.relativity)
  • Re: complex numbers
    ... >> sqrtmay be defined by programming languages to be "the ... >> positive square root", allowing the programmer to assign whatever ... >> signthe programmer chooses. ... > sqrt is the positive root of a positive number. ...
    (sci.physics.relativity)
  • Re: complex numbers
    ... sqrtmay be defined by programming languages to be "the positive square root", allowing the programmer to assign whatever signthe programmer chooses. ...
    (sci.physics.relativity)
  • Re: complex numbers
    ... >> You can see that unless you keep straight just what ... sqrt() may be defined by programming languages to be "the ... positive square root", allowing the programmer to assign whatever ... signthe programmer chooses. ...
    (sci.physics.relativity)
  • Re: Forth PARANOIA
    ... Addition/Subtraction neither rounds nor chops. ... Test for sqrt monotonicity. ... "Square root is neither chopped nor correctly rounded", ...
    (comp.lang.forth)