Devon McCormick wrote:
> NB. I stumbled across this trying to help my daughter with her
> NB. homework of finding a zero for the following function.  I attempted to
> NB. cheat by graphing it but was puzzled by what I got until I realized
> NB. that, applied to negatives, this function returns complex numbers and
> NB. the plot package treats these as 2-D point pairs.
> NB. I actually solved it for one root by inspection.
>

I've been burned on this a few times.  I suggest:

(a) Use clean (in ~system/packages/math/mathutil.ijs) to zero small values
in numerical calculations.

(b) If you are trying to supply real data to plot, use [EMAIL PROTECTED] to get 
the
real part, not 9&o. (which produces results whose internal type is
complex).

Best wishes,

John



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