Re: This should evaluate to zero

*To*: mathgroup at smc.vnet.net*Subject*: [mg40018] Re: This should evaluate to zero*From*: atelesforos at hotmail.com (Orestis Vantzos)*Date*: Sun, 16 Mar 2003 02:20:37 -0500 (EST)*References*: <b4mnhk$iig$1@smc.vnet.net> <b4pg2c$c06$1@smc.vnet.net> <b4s8k6$iec$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

In any case, FullSimplify[(3363+2378*Sqrt[2])^1/10] does return 1+Sqrt[2] Orestis jf.alcover at bdpme.fr (jf alcover) wrote in message news:<b4s8k6$iec$1 at smc.vnet.net>... > atelesforos at hotmail.com (Orestis Vantzos) wrote in message news:<b4pg2c$c06$1 at smc.vnet.net>... > > Actually, ArcSinh[1] is equal to Log[1+Sqrt[2]] > > Orestis, > > You're right, and Mathematica 'knows' that but it seems not to know > that it's also equal to Log[3363+2378*Sqrt[2]]/10 > > The most straightforward solution to this trouble seems to be the one provided > by Vladimir Bondarenko <vvb at mail.strace.net> : > > In[1] := expr = ArcSinh[1]-Log[3363+2378*Sqrt[2]]/10; > > In[2] := FullSimplify[expr, ComplexityFunction -> Length] > > Out[2] = 0 > > ------ > jfa