Help with rules;

*To*: mathgroup at smc.vnet.net*Subject*: [mg6014] Help with rules;*From*: Gadi Oron <oron at tremois.pmmh.espci.fr>*Date*: Tue, 11 Feb 1997 01:20:02 -0500*Organization*: Acces regional Ile-de-France (Univ. Paris VI/VII) - France*Sender*: owner-wri-mathgroup at wolfram.com

Hi there guys, I'm using MM 2.2 under unix, I have this expression 2 3 2 Sqrt[c2 - 6 c4] Sqrt[c2 - 6 c2 c4] Sqrt[-2 c4 + 5 c2 c6] Pi Out[56]= -------------------------------------------------------------- 2 Sqrt[2] c2 Sqrt[2 c4 - 5 c2 c6] In[57]:= InputForm[%] Out[57]//InputForm= ((c2^2 - 6*c4)^(1/2)*(c2^3 - 6*c2*c4)^(1/2)*(-2*c4^2 + 5*c2*c6)^(1/2)*Pi)/ (2^(1/2)*c2*(2*c4^2 - 5*c2*c6)^(1/2)) And i want to simplify it by replacing Sqrt[-2 c4^2 - 5 c2 c6]/Sqrt[-the same] by I, How come : % /. Sqrt[x_]/Sqrt[-x]-> I does not work ??!! Help!!! Thanx /\/\/\/\/\/\/\/\/\/\/\/>> Gadi ORON <<\/\/\/\/\/\/\/\/\/\/\/\/\ | EMAIL : oron at pmmh.espci.fr :::: oron at clipper.ens.fr | | Homepage : http://pmmh.espci.fr/home/oron/WWW/personal.html | | fido : 2:325/302.8 | | Soyez braves - be brave. | /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/