Eliminating (-1)^2
- To: mathgroup at smc.vnet.net
- Subject: [mg16402] Eliminating (-1)^2
- From: "Nicolas B.E. Sawyer" <nbes at eee.nott.ac.uk>
- Date: Thu, 11 Mar 1999 02:17:02 -0500
- Organization: University of Nottingham
- Sender: owner-wri-mathgroup at wolfram.com
1) How do I get Mathematica to eliminate factors of (-1)^2. Specifically
I want to replace occurrences of (-(1-a)x -a y)^2 by ((1-a)x +a y)^2
within an expression?
2) Using InputForm
In[132]:=
(-(1 - a)x - a y)^2
Out[132]=
2
(-((1 - a) x) - a y)
but with StandardForm
In[130]:=
\!\(\((\(-\((1 - a)\)\) x - a\ y)\)\^2\)
Out[130]=
2
((-1 + a) x - a y)
Why the difference in the results and why doesn't either give the
following?
2
((1 - a) x + a y)
Finally, since
Simplify[(-x - y)^2]
gives
2
(x + y)
why does
Simplify[(-(1 - a)*x - a*y)^2]
yield
2
((-1 + a) x - a y) ?
--
Nicolas B.E. Sawyer
Department of Electrical and Electronic Engineering,
University of Nottingham,
University Park,
Nottingham,
NG7 2RD.
Tel: +44 115 9515151 ext 12028
Fax: +44 115 9515616
E-mail: nbes at eee.nottingham.ac.uk