Plot2d bugs 694770 and 710677



> 
> I don't know much about that (does any CAS have pole finding routines?)

... Looking for f= infinity by   solve(1/f=0,..)


> but that problem reminds me of a silly question I've been wanting to
> ask:
> 
> in the case of something like:
> 
>                         (x + 2) (x + 1)                            
>                         ---------------
>                              x + 1
> 
> Maxima will simplify this to x+2.  But, as written, doesn't this
> expression have a hole at x=-1?  It will do the x+2 thing everywhere
> else - is it OK to simplify because it's a case of zero over zero?  I
> thought that didn't evaluate to one mathematically.
> 
> I'm assuming I'm just a dork, but can someone set me straight?

I think the distinction is that in the field of rational functions
with removable singularities removed, what you have above is x+2.

If you want to talk about what this means as a program, you can make
up lots of different things.  The canonical example here is computing
sin(x)/x at x=0, which every calculus student knows has a limit as x->0
of 1.  Yet the dumb computer probably does "division by zero".
RJF

> 
> CY
> 
> 
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