Re: Need help with solving problem
- To: mathgroup at smc.vnet.net
- Subject: [mg5370] Re: [mg5339] Need help with solving problem
- From: Sherman Reed <Sherman.Reed at worldnet.att.net>
- Date: Thu, 5 Dec 1996 14:50:15 -0500
- Sender: owner-wri-mathgroup at wolfram.com
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!
>
>
>