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Alan Beban Alan Beban is offline
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Default Excel 2003 SP2 computes the power of a negative number wrong.

Giovanni Ciriani wrote:
Then let me ask you a question. Why should -A1^4-1 evaluate to a different
number than 1-A4^4 ? (-255 vs 257 for A1 equal to -4).

This striking difference goes counter the rule of commutativity additions
established several centuries ago (if not millenia): the order of the number
being added should not change the result of an addition.


I think you meant -A1^4+1. And the answer, which you are refusing to
acknowledge even though it's been pointed out to you a couple of times,
is that the minus sign in -A1^4-1 is a negation operator, not a
subtraction operator, so commutativity of subtraction is not relevant.
To see commutativity in action compare =1-(-A1^4)-2 with
=1-2-(-A1^4),where the minus signs preceding the parenthetical and 2
are, in fact, subtraction operators.

Alan Beban

"Arvi Laanemets" wrote:

Hi

Rewrite the equation as
=((-1)*(-4))*((-1)*(-4))*((-1)*(-4))*((-1)*(-4))

What do you get as result?

Maybe you wanted
=-(A1^4)


Arvi Laanemets


"Giovanni Ciriani" <Giovanni wrote in
message ...
A1 contains -4.
B1 contains the expression -A1^4
The result is supposed to be -256, but instead it is 256.

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