[Date Index]
[Thread Index]
[Author Index]
Re: Trig identity oscillations
*To*: mathgroup at smc.vnet.net
*Subject*: [mg47710] Re: Trig identity oscillations
*From*: adam.smith at hillsdale.edu (Adam Smith)
*Date*: Fri, 23 Apr 2004 02:30:38 -0400 (EDT)
*References*: <c67q7l$gum$1@smc.vnet.net>
*Sender*: owner-wri-mathgroup at wolfram.com
You are correct that Cos[t+5 Pi/6]/Sin[t+Pi/3] = 1.
What is happening is that the Plot function is numerical. As is
substitutes in various values for t you end up with a very small
number divide by another very small number. The rounding that occurs
in the numerical evaluations is what causes the unexpected behavoir.
Try Simplify[Cos[t+5 Pi/6]/Sin[t+Pi/3]] and you will find that
Mathematica returns the expected 1. In general it is useful to
simplify any complicated function before plotting.
Plot[Simplify[Cos[t+5 Pi/6]/Sin[t+Pi/3]],{t,0,2 Pi}]
Adam Smith
mathma18 at hotmail.com (Narasimham G.L.) wrote in message news:<c67q7l$gum$1 at smc.vnet.net>...
> Should it not be a more placid -1 ?
> Plot[Cos[t+5 Pi/6]/Sin[t+Pi/3],{t,0,2 Pi}]
Prev by Date:
**Matrix expansion**
Next by Date:
**Re: NIntegrate or For or Special Function?**
Previous by thread:
**RE: Trig identity oscillations**
Next by thread:
**NIntegrate or For or Special Function?**
| |