----Original Message----
>From: David Daney
>Sent: 26 May 2005 18:23
> Dave Korn wrote:
>
>> " Identities such as
>> sin(x)^2 + cos(x)^2 === 1
>> are only valid when 0 <= x <= 2*PI"
>>
>
> It's been a while since I studied math, but isn't that particular
> identity is true for any x real or complex?
>
> David Daney,
Yes, that was solely an example of the difference between 'identities' and
'functions', for illustration, in case there was any ambiguity in the
language, but was not meant to be an example of an *actual* identity that
has a restriction on the valid range of inputs. Sorry for not being
clearer.
cheers,
DaveK
--
Can't think of a witty .sigline today....
