Hold and Equal

*To*: mathgroup at smc.vnet.net*Subject*: [mg73715] Hold and Equal*From*: Murray Eisenberg <murray at math.umass.edu>*Date*: Mon, 26 Feb 2007 06:12:41 -0500 (EST)*Organization*: Mathematics & Statistics, Univ. of Mass./Amherst*Reply-to*: murray at math.umass.edu

How can I produce in an Output cell (under program control) an expression like the following, (a+b)^2 = a^2+ 2 a b + b^2 where instead of the usual Equal (==) I get a Set (=), as in traditional math notation? I want to input the unexpanded (a+b)^2 and have the expansion done automatically. Of course, I can try something like the following: (a+b)^2 == Expand[(a+b)^2]) So how do I convert the == to =? Of course ((a + b)^2 == Expand[(a + b)^2]) /. Equal -> Set gives a Set::write error. And (Hold[(a + b)^2 == Expand[(a + b)^2]]) /. Equal -> Set doesn't actually evaluate the Expand part and leaves the "Hold" wrapper. -- Murray Eisenberg murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 549-1020 (H) University of Massachusetts 413 545-2859 (W) 710 North Pleasant Street fax 413 545-1801 Amherst, MA 01003-9305

**Follow-Ups**:**Re: Hold and Equal***From:*"Chris Chiasson" <chris@chiasson.name>

**Re: Hold and Equal***From:*Carl Woll <carlw@wolfram.com>