2 Mar
2012
2 Mar
'12
12:07 p.m.
Hi, Tomasz, One of the common reasons for such problem is that your expression still contains some variables. Make a debug print of it and check if it is the case. Good luck! Vladimir -- Vladimir V. Kisil email: kisilv@maths.leeds.ac.uk www: http://www.maths.leeds.ac.uk/~kisilv/ Book: Geometry of Mobius Transformations http://www.icpress.co.uk/mathematics/p835.html