On 12/02/2012 07:43 AM, Raymond Toy wrote:
> For a < 0, we have z =|a|*exp(-%i*%pi/2), so
> sqrt(z^2) = sqrt(|a|^2*exp(+%i*%pi)) =|a|*exp(+%i*%pi/2). Thus
> sqrt(z^2) =|a|*exp(+%i*%pi/2)/(a*exp(-%i*%pi/2)) =|a|/a*exp(%i*%pi)
> = 1.
Shouldn't this be:
For a < 0, we have z =|a|*exp(-%i*%pi/2),
so sqrt(z^2) = sqrt(|a|^2*exp(+%i*%pi)) =|a|*exp(+%i*%pi/2).
Thus sqrt(z^2)/z =|a|*exp(+%i*%pi/2) / (|a|*exp(-%i*%pi/2)) = (|a|/|a|)*exp(%i*%pi) = -1
?
Jaime