Tom Melly wrote:

> > NO!! 1+2*3-4 is three, only three, exactly three, no more, no less, and
> most
> > certainly not and NEVER five. If you meant (1+2)*3-4, that would be
> analagous to
> > me typing orange and meaning purple. Anyone who types 1+2*3-4 and expects
> 5 is
> > an idiot.
> >
>
> I disagree. Anyone who types 2*1.5 and expects 5 is an idiot. Typing 1+2*3-4
> and expecting 5 just means that they don't know the conventions. The
> conventions exist because intelligence alone cannot resolve the issue.

I still disagree. Mathematics REQUIRES conventionality. There can be NO
ambiguity in mathematics. It operates on the idea of proof through logic.

There are reasons for the order of operations. Every multiplication operation
takes parts of the same thing; length*width=area of *one* face on a cube, or
average_velocity*time=displacement. Addition and subtraction however take
multiples of something; you sum multiple faces to get the total surface area, et
al. Of course it is not always this simple, but that's why we use parentheses.
The parentheses show us clearly, visually and unambiguously that an operation is
being used as one piece in a larger operation.

If your calculator is giving you five it is merely a limitation of the
technology. The manual probably states clearly that five is techincally wrong,
and shows what the calculator is *really* doing. Any scientific calculator obeys
order of operations, and even the older ones will expect that you request the
result before the computation is complete. Instead the cheap calcs think you
want a result after every operation, then discard everything you typed in.


--
David Fontaine  <dav### [at] faricynet>  ICQ 55354965
My raytracing gallery:  http://davidf.faricy.net/

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