Re: Hold and Equal

*To*: mathgroup at smc.vnet.net*Subject*: [mg73747] Re: Hold and Equal*From*: bghiggins at ucdavis.edu*Date*: Tue, 27 Feb 2007 05:48:54 -0500 (EST)*References*: <erufqm$s7j$1@smc.vnet.net>

Murray, Try this HoldForm[(a + b)^2 = z] /. z -> Expand[(a + b)^2] (a + b)^2 = a^2 + 2*a*b + b^2 Cheers, Brian On Feb 26, 3:20 am, Murray Eisenberg <mur... at math.umass.edu> wrote: > 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 mur... 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: Re: Hold and Equal***From:*Murray Eisenberg <murray@math.umass.edu>