Re: FullSimplify fails for very large numbers and powers
- To: mathgroup at smc.vnet.net
- Subject: [mg89938] Re: FullSimplify fails for very large numbers and powers
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Wed, 25 Jun 2008 06:23:13 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <g3q7hv$af3$1@smc.vnet.net>
Paul Schneider wrote: > Dear newsgroup, > > FullSimplify (Mathematica 6 and 5.2) does not simplify the expression: > > (-1505046085600344525396741688335403635402237542400000000000000000000000000*(-kth > + 2*k*r)^187*(kth - 2*k*r + 6*s*(-2*k*rho + s))^6* > (kth - 2*k*r + 8*s*(-2*k*rho + s))^6*((k^196*(kth + > s^2))/(3010092171200689050793483376670807270804475084800000000000000000000000000*(-kth > + 2*k*r)^187* > (kth - 2*k*r + 6*s*(-2*k*rho + s))^6*(kth - 2*k*r + 8*s*(-2*k*rho > + s))^6) + (k^196*(4*k^2 - 4*k*rho*s + s^2))/ > > (3010092171200689050793483376670807270804475084800000000000000000000000000*(-kth > + 2*k*r)^187*(kth - 2*k*r + 6*s*(-2*k*rho + s))^6* > (kth - 2*k*r + 8*s*(-2*k*rho + s))^6)))/k^199 > > to the much nicer > > -(4*k^2 + kth - 4*k*rho*s + 2*s^2)/(2*k^3) > > Do you have tips on how I could achieve this? > > Thank you, > > Paul > > PS: the expressions are in InputForm. Somehow the power signs get lost > when pasting from Thunderbird. Pasting from Kmail seems to work. > Since you have a rational expression (I have called it expr1 in the example below), it is always good to try *Together[]*, as you can see: In[2]:= expr1 // Together Out[2]= (-4 k^2 - kth + 4 k rho s - 2 s^2)/(2 k^3) Regards, -- Jean-Marc