Re: Simple problem for math wiz
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg1708] Re: Simple problem for math wiz
- From: porfy at odin.gsfc.nasa.gov (Porfirio Beltran)
- Date: Wed, 19 Jul 1995 00:13:39 -0400
- Organization: NASA Goddard Space Flight Center -- Greenbelt, Maryland USA
In article <DBKwIr.2qv at wri.com>, nomail at me.net (REVEAL) wrote:
> Anyone here know how to find the solution set to: sin^2x+sinx-1=0 ? the
trick, that is?
> (limited to trig & algebra)
Is this is the function you want to solve?
In[1] Sin[x]^2 + Sin[x] - 1 == 0
Out[1] -1 + Sin[x] + Sin[x]^2 == 0
If so, I'm sure you know that the Mma Function 'Solve' doesn't cut it:
In[2] Solve[Sin[x]^2 + Sin[x] - 1 == 0]
Out[2] {{Sin[x] -> (-1 - 5^(1/2))/2},{Sin[x] -> (-1 + 5^(1/2))/2}}
Use 'FindRoot':
In[3] FindRoot[Sin[x]^2 + Sin[x] - 1 == 0, {x,0}]
Out[3] {x -> YOU FIND IT!}
Porfy.
** "Because is my nature..." - The Scorpion. **