Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2006
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2006

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

Search the Archive

Re: Assumptions for Trigonometry Inequalities

  • To: mathgroup at smc.vnet.net
  • Subject: [mg71375] Re: Assumptions for Trigonometry Inequalities
  • From: "dimitris" <dimmechan at yahoo.com>
  • Date: Thu, 16 Nov 2006 00:53:05 -0500 (EST)
  • References: <ejev72$1nt$1@smc.vnet.net>

Looks strange because Mathematica evaluates correctly e.g.

Sin /@ Range[-Pi, 0, Pi/6]
{0, -(1/2), -(Sqrt[3]/2), -1, -(Sqrt[3]/2), -(1/2), 0}

Anyway, if you try

Simplify[Sin[gamma] < 0, Pi < gamma < 2*Pi]
True

works fine.


Martin Schoenecker wrote:
> Hello,
>
> the Sin of a real number between zero and Pi should be positive, as
> Simplify finds out, too.
>
> In[133]:= Simplify[Sin[gamma]>0,0<gamma<Pi]
> Out[133]= True
>
> As well, the Sin of a number between -Pi and 0 is negative, but why
> doesn't Simplify evaluate it?  The Less implies that the variable is
> real, I think, however stating it explicitly doesn't change the result.
>
> In[134]:= Simplify[Sin[gamma]<0,-Pi<gamma<0]
> Out[134]= Sin[gamma]<0
> 
> Are there any hints on that?
> Thank you,
> Martin


  • Prev by Date: Re: comparing finite fields elements with == or != doesn't work?!?!
  • Next by Date: RE:Need Help: Can not use Ticks under PolarPlot
  • Previous by thread: Re: VerifySolutions setting
  • Next by thread: RE:Need Help: Can not use Ticks under PolarPlot