Re: Need help with solving problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg5361] Re: [mg5339] Need help with solving problem*From*: "Dr. Sergio Miguel Terrazas Porras" <sterraza at campus.cdj.itesm.mx>*Date*: Thu, 5 Dec 1996 14:50:10 -0500*Sender*: owner-wri-mathgroup at wolfram.com

Ingimar, The second line is wrong 2*(2^x)=2^(x+1) and not 4^x Saludos Sergio Terrazas On Wed, 27 Nov 1996, Ingimar Vvlundarson wrote: > Can anyone help me with this problem? > > (4^x)+(2^x)-2=0 > > Everyone can see that x=0 but: > > (4^x)+(2^x)-2=0 => > 2*(2^x)+(2^x)-2=0 => > 2y+y-2=0 => ;(let y=2^x) > 3y=2 => > y=2/3 => > 2^x=2/3 => ;(let 2^x=y) > lg(2^x)=lg(2/3) => > x*lg(2)=lg(2/3) => > x=lg(2/3)/lg(2) Which is not true!!! > > Am I doing something wrong? > > Please E-mail an answer to: > ingimar.volundarson at mailbox.swipnet.se > > Thanx in advance! > > >