       Re: Tracing

• To: mathgroup at smc.vnet.net
• Subject: [mg6677] Re: [mg6612] Tracing
• From: Richard Finley <trfin at fiona.umsmed.edu>
• Date: Wed, 9 Apr 1997 09:15:48 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

```Ivan
There are several ways to do what you want.  To find the points of
intersection use:
In:= Solve[Sqrt[x]==Abs[x],x]

This will give the result x=0 and x=1 which is correct.  You could also use
FindRoot. To plot the functions and see where they intersect the following
command will do the trick:

In:= Plot[{Sqrt[x],Abs[x]},{x,0,2}]

This of course is a very simple example.  For more complicated equations
where the answer is not so obvious you have to be more diligent and creative.

RF

At 11:07 PM 4/5/97 -0500, you wrote:
>Folks,
>
>
>
>I just got Mathematica 3.0 for the Macintosh student version(2 plus
>months).
>
>I want to do something that should be available in this powerful
>program.
>
>I want to trace a 2D graph to recheck if my manual math was correct.
>Items such as intercept points and such.
>
>I got the users manual(thick book) and such but there is not much
>information other than manually tracing using the cmd-click on the graph
>to hopefully get the about right information(not).
>
>I also have a TI-85 which does this real fine. My Graphing Caluculator
>that was included with the Macintosh does real good(not exact).
>
>Here is the thing I want to know:
>
>I have a graph of sqrt[x], and abs[x]
>I want to know graphicly and by hard math what the intercept point are.
>
>I want to know the two point exactly where they intercept at. How do I
>do the math through mathemathica 3.0 and show graphicly where they are.
>If Mathemathica 3.0 does not do this please let me know.
>
>
>Note: I am not taking any math classes yet I will be in about a week. I
>am just rying to brush up on my math before I start up again.
>
>
>
>
>
>
>
>Sincerely,
>
>
>
>
>
>Ivan G. Burch II aka enforcer