Re: bug???
- To: mathgroup at smc.vnet.net
- Subject: [mg45244] Re: bug???
- From: bobhanlon at aol.com (Bob Hanlon)
- Date: Tue, 23 Dec 2003 05:13:36 -0500 (EST)
- References: <bs3nhd$io4$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
expr = x^802+4x^403+2x^2-3;
The expression appears somewhat ill-behaved in the vicinity of the roots
Plot[expr, {x,-1.1,1.1}, PlotRange->{-4,1}];
Use FindRoot
soln = FindRoot[expr == 0,{x, #}, WorkingPrecision -> 25]& /@ {-1.01, 0.99}
{{x -> -1.00362087434639900230773988491141313065`25},
{x -> 0.99645520502905074430271593389748558116`25}}
expr /. soln
{1.22728701669`0*^-22, 1.82364069596`0.6216*^-22}
Bob Hanlon
In article <bs3nhd$io4$1 at smc.vnet.net>, "ANDY" <wangzhengyao at hotmail.com>
wrote:
<< please running the next Expression:
Timing[NSolve[x^802 + 4x^403 + 2x^2 - 3 == 0, x, 4]]
in Mathematica4.1 and Mathematica 5.