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Error in integrals?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg9482] Error in integrals?
  • From: "Clifford J. Nelson" <nelsoncj at gte.net>
  • Date: Thu, 6 Nov 1997 02:40:26 -0500
  • Organization: gte.net
  • Sender: owner-wri-mathgroup at wolfram.com

Mathematica 3.0 on a PowerMac 7200/90 88MB Mac OS 8 gives different
results for Integrate vs. NIntegrate.

Here is one example.

ior[m_] := 1/3*(2*Sqrt[3]*Sqrt[(-1 + m^2)^2/(1 + m^2)^4] +
 Sqrt[(Sqrt[3] - 6*m - Sqrt[3]*m^2)^2/(1 + m^2)^4] +  Sqrt[(Sqrt[3] +
6*m - Sqrt[3]*m^2)^2/(1 + m^2)^4])

In[31]:=
N[Integrate[ior[m],{m,0,1}]]

Out[31]=
-0.42265

In[32]:=
NIntegrate[ior[m],{m,0,1}]

Out[32]=
1.73206

What am I doing wrong ? Which answer is correct ?

Cliff Nelson




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