Re: Problem with Limit
- To: mathgroup at smc.vnet.net
- Subject: [mg66833] Re: [mg66805] Problem with Limit
- From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
- Date: Thu, 1 Jun 2006 06:54:25 -0400 (EDT)
- References: <200605311030.GAA13862@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
On 31 May 2006, at 19:30, Tony Harker wrote: > > Can anybody explain why, for > > t =Sqrt[(k*m1 + k*m2 + m1*g + m2*g - > (1/2)*Sqrt[4*(m1 + m2)^2*(k + g)^2 - 16*k*m1*m2*(k + 2*g)])/ > (m1*m2)]/(1 + (k*m1 - k*m2 + m1*g - m2*g + > (1/2)*Sqrt[4*(m1 + m2)^2*(k + g)^2 - 16*k*m1*m2*(k + > 2*g)])^2/ > (4*m1*m2*g^2)) + Sqrt[(k*m1 + k*m2 + m1*g + m2*g + > (1/2)*Sqrt[4*(m1 + m2)^2*(k + g)^2 - 16*k*m1*m2*(k + 2*g)])/ > (m1*m2)]/(1 + ((-k)*m1 + k*m2 - m1*g + m2*g + > (1/2)*Sqrt[4*(m1 + m2)^2*(k + g)^2 - 16*k*m1*m2*(k + > 2*g)])^2/ > (4*m1*m2*g^2)); > > Limit[t, g -> 0] > Limit[Together[t], g -> 0] > > both give zero, whereas > > Limit[Simplify[Together[t]], g -> 0] > > gives a non-zero result? This is with Mathe4matica 5.2. > > > Dr A.H. Harker > Department of Physics and Astronomy > University College London > Gower Street > London > WC1E 6BT > > Mathematica 5.1 gives 0 in all of the above cases. Moreover: In[48]:= t + O[g]^1 Out[48]= O[g]^1 which agrees with it. Andrzej Kozlowski Tokyo, Japan