MathGroup Archive 2000

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

Search the Archive


  • To: mathgroup at
  • Subject: [mg25602] limits
  • From: "Tom De Vries" <tdevries at>
  • Date: Wed, 11 Oct 2000 03:50:40 -0400 (EDT)
  • Sender: owner-wri-mathgroup at

Hello all,

Forgive the simple questions here.  I'm a high school mathematics teacher
having a go at teaching calculus so my knowledge is limited.  Our class is
using Mathematica and I was wondering about the interpretation of limits
using Mathematica.

Limit[1/(x - 2), x -> 2]

gives me an answer of infinity.   However,  taking the limit from both
directions shows that the limit is different coming from either side of 2.  

Limit[1/(x - 2), x -> 2,  Direction -> 1]

Limit[1/(x - 2), x -> 2, Direction -> -1]

When I ask Mathematica to take a limit at 2, should I not expect it to give
me an answer that would indicate that the limit does not exist since it is
different coming from above and below?

Thanks for any help you might provide!


Tom De Vries
Edmonton, Alberta

  • Prev by Date: Making Big Substitution List
  • Next by Date: integral of Bessel function, bug in Mathematica 4.0
  • Previous by thread: RE: Making Big Substitution List
  • Next by thread: strange problem about colors