MathGroup Archive 2000

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

Search the Archive

Re: Vertical Tangents

  • To: mathgroup at
  • Subject: [mg25855] Re: Vertical Tangents
  • From: Tom Moriarty <tjmor at>
  • Date: Wed, 1 Nov 2000 01:25:40 -0500 (EST)
  • References: <8t64dv$> <yTLK5.273$>
  • Sender: owner-wri-mathgroup at

Once again I want to thank all those who responded to my question, your
suggestions certainly solved my problem.

Many thanks.

Albert Retey wrote:

> Tom Moriarty wrote:
> >
> > This group was very helpful on my last question and I hope you will be
> > willing to once again come to the aid of a teacher trying to illustrate
> > to calculus students tangents to implicit plots.  By the way, I
> > purchased Mathematica on my own, it is not available to me at school -
> > so I plot at home and Xerox handouts for the kids.  I have been able to
> > show them various implicit plots and tangents to them - for example
> > ImplicitPlot[{x^2 + x*y + y^2==7, y == 2*Sqrt[7/3]},{x,-5,5}] which
> > clearly shows the ellipse and one of the horizontal tangents (as asked
> > for in the textbook problem).  But the problem also asked for the
> > vertical tangents, one of which would be x == 2*Sqrt[7/3], but I get the
> > message that this equation does not have a single variable other than
> > x.  Is there any way to plot a vertical line?
> I don't have expericence with ImplicitPlot, so I don't know whether you
> can make it plot what you need, but a simple way to produce a vertical
> line is:
> p = ParametricPlot[{2*Sqrt[7/3], t}, {t, -10, 10}]
> Then use Show to put it together with your ImplicitPlots
> Albert

  • Prev by Date: Re: combinatoric card problem
  • Next by Date: Re: Is it possible to plot a point a time on the same graph in Mathematica?
  • Previous by thread: Re: combinatoric card problem
  • Next by thread: Re: Is it possible to plot a point a time on the same graph in Mathematica?