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Myrna Larson
 
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Why? Because that's the way they wrote it. And no, there's no way to change
this. You must write your Excel formulas to a suit the way Excel does the
calculations.

On Mon, 21 Feb 2005 19:47:02 -0800, "Atreides" <atreides1AThotmailD0Tcom
wrote:

I've recently noticed that Excel flies in the face of standard scientific,
mathematical and engineering convention in the calculation of powers for
numbers that are then multiplied by a negative.

The convention of mathematics, "BIMDAS" (or similar acronyms), states that
_I_ndices (or powers, or exponents), should be calculated before
_M_ultiplication. Because of this, the following is accepted as correct:

-3^2 = -9.

This is because it is the equivalent of (-1) * 3^2 = -1 * 9 = -9

However, Excel chooses to recognise this as (-3)^2 = 9.

This error is particularly problematic when doing algebraic computations in
such a tool as Mathematica and then copying the result into Excel in input
form. That is,

-x^2 - -A1^2
- -A1^2
(Mathematica) (Mathematica with reference substituted) (Excel)

To correct the error, one must manually change it to: -(A1^2)

QUESTIONS
1: Why does Excel have this convention!
2: Is there any way to change it/make is more convenient?

I've only recently noticed this (which is quite scary to think how many
errors I may have made in the past!)

Thanks for your time,

Cheers,
Peter