MathGroup Archive 1996

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Need help with solving problem


At 06:47 AM 11/27/96 +0000, you 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 =>                   THIS STEP IS NOT TRUE IT SHOULD BE
                                        2*(2^(2*x-1))+(2^x)-2
>2y+y-2=0 =>      ;(let y=2^x)          WHICH MAKES THE REST WRONG
>3y=2 =>                                TRY IT IN MMA
>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!
>
>
>



  • Prev by Date: Re: Need help with solving problem
  • Next by Date: Q:Nicer than: Function[x,MapAt[Im,x,2]]/@data
  • Previous by thread: Re: Need help with solving problem
  • Next by thread: Re: Need help with solving problem