caps complex tests



Speaking of interpretation. radcan(sqrt(y^2-2*y+1)) is using sqrt(x^2)=x so 
you get y-1.  Well, why not 1-y instead as your example below points out?

radcan(sqrt(y^2-2*y+1));
-> y-1


-----Original Message----- 
From: Richard Fateman
Sent: Sunday, November 14, 2010 5:54 PM
To: Richard Hennessy
Cc: Maxima - list
Subject: Re: [Maxima] caps complex tests

On 11/14/2010 2:42 PM, Richard Hennessy wrote:
> I guess, under the interpretation that sqrt(x^2) = x then this answer is 
> right.
>
Well, if sqrt(x^2)=x,  then how do you feel about

             sqrt( (1-y)^2)  =   1-y  ?

            and
             sqrt((y-1)^2)   = y-1  ?


Of course,  (1-y)^2 = (y-1)^2,  so  the sqrt()   could be either of
those two things, or a third, which is abs(1-y)  which chooses half of
one answer and half of the other.

RJf