Re: Mathematica Weirdness
- To: mathgroup at smc.vnet.net
- Subject: [mg116694] Re: Mathematica Weirdness
- From: István Zachar <zac at freemail.hu>
- Date: Thu, 24 Feb 2011 06:22:30 -0500 (EST)
- References: <ik2nab$9kk$1@smc.vnet.net>
My machine (Mathematica 8.0.0.0, Win 7) gives:
In[1]:= Integrate[1000000*Exp[x^2 - 12*x]*x^14, {x, 0, 1}] // N
Integrate[1000000*Exp[x^2 - 12*x]*x^14, {x, 0., 1}] // N
NIntegrate[1000000*Exp[x^2 - 12*x]*x^14, {x, 0, 1}]
Out[1]= -0.909408
Out[2]= -0.739909
Out[3]= 2.74821
On Feb 23, 11:25 am, Steve Heston <shes... at rhsmith.umd.edu> wrote:
> My question is why I get a negative integral of a positive
> function?
>
> Integrate[1000000*Exp[x^2-12*x]*x^14,{x,0,1}]//N
> Integrate[1000000*Exp[x^2-12*x]*x^14,{x,0.,1}]//N
> NIntegrate[1000000*Exp[x^2-12*x]*x^14,{x,0,1}]
>
> The first line gives a negative answer, while the second two lines give
> identical positive answers. Something is strange here.
>
> Steve
>
> Steven L. Heston
> Associate Professor
> Finance Department
> Robert H. Smith School of Business
> 4447 Van Munching Hall Van Munching Hall
> University of Maryland
> College Park, MD 20742-1815
> 301-405-9686 TEL
> 301-405-0359 FAX
> shes... at rhsmith.umd.eduhttp://www.rhsmith.umd.edu