Mathematica 9 is now available
Services & Resources / Wolfram Forums
MathGroup Archive
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2002

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Q: Simplify with "much less" assumptions

  • To: mathgroup at
  • Subject: [mg35622] Re: [mg35600] Q: Simplify with "much less" assumptions
  • From: "Xuguang\(Heather\) Zhang" <xuguang_zhang at>
  • Date: Tue, 23 Jul 2002 01:51:29 -0400 (EDT)
  • References: <>
  • Sender: owner-wri-mathgroup at

AW: [mg35600] Q: Simplify with "much less" assumptionsThank you, bode. 
Maybe the last example I gave is too simplified. In fact, the problem I 
always meet with is as follows:
F(x,y,w,z) is a function of x,y,w and z where x,y,w and z are greater 
than zero. I want to simplify F(x,y,w,z) under the assumption that x is 
much less than y.
Can you please tell me how to do that? Thank you.

----- Original Message -----
  From: Matthias.Bode at
To: mathgroup at
  Sent: Monday, July 22, 2002 8:48 AM
  Subject: [mg35622] AW: [mg35600] Q: Simplify with "much less" assumptions

  Hello Heather,


  1 + x^2 /. {x -> 0}

  It will give you the 1 you wish.

  Best regards,
  Matthias Bode.

  Von: Xuguang(Heather) Zhang [mailto:xuguang_zhang at]
  Gesendet: Montag, 22. Juli 2002 08:11
  An: mathgroup at
  Betreff: [mg35600] Q: Simplify with "much less" assumptions

  Hello, everybody,

  I have one question regarding simplify answer with assumptions. For
  example, I have "1+x^2". The assumptions is  x is much much less than 
  Therefore x^2 can be neglected under the above assumption. What I get
  after simplification should be "1" only. Can anybody tell me how do 
  in Mathematica? It seems there is no "much less" or "much greater"
  symbol in Mathematica. Thank you all.


  • Prev by Date: Number crunching testreport 4th edition
  • Next by Date: Slow iteration in a functional program
  • Previous by thread: Re: Q: Simplify with "much less" assumptions
  • Next by thread: RE: Re: Q: Simplify with "much less" assumptions