On 17-May-2012 21:50:17 Petr Savicky wrote:
> On Thu, May 17, 2012 at 01:53:39PM -0500, Pei-Ling Lin wrote:
>> Hi all,
>>
>> I need to solve this following equation which the unknown value (here is
>> "a") is on the exponent place, could anybody please help me to figure it
>> out? I tried to use lm.sol() or solve() function but it doesn't work......
>>
>> Thanks for help,
>> Peiling
>>
>>
>> (x, y) = (2.21, 1.01)
>>
>> y = 1 + x - ( 1 + (x)^a)^(1/a)
>
> Hi.
>
> First, plot the function
>
> f <- function(a) { 1 + x - ( 1 + (x)^a)^(1/a) - y }
> x <- 2.21
> y <- 1.01
> a <- seq(0.1, 20, length=1000)
> plot(a, f(a), ylim=c(-0.2, 0.2), type="l")
> abline(h=0)
>
> This suggests, that there is no root. This may also be obtained
> analytically.
>
> Hope this helps.
>
> Petr Savicky.
Well, certainly no solution for Y > 1. But if y < 1 then there
is a solution. Was the problem stated correctly?
Ted.
-------------------------------------------------
E-Mail: (Ted Harding) <ted.hard...@wlandres.net>
Date: 17-May-2012 Time: 23:27:09
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