[Newbie:] How to discard higher orders of variables?
Subject: [Newbie:] How to discard higher orders of variables?
From: Stavros Macrakis
Date: Wed, 11 Jul 2007 14:58:15 -0400
On 7/11/07, Daniel Lakeland <dlakelan at street-artists.org> wrote:
>
> > My problem is that I want to discard higher order terms within an
> expression
> > as it is often done when simplifying analytical equations in
> engineering.
>
> often this is done by ratsubst if the equation is simple.
Only if the expression is already in the appropriate form. sqrt(1+x^2) and
1/(x+1) are very simple expressions, but ratsubst is not the tool to use to
see that for x near 0, they behave like 1+x^2/2+... and 1-x+x^2+...
-s