Author |
Topic: find x in ^(1/4) equation (Read 445 times) |
|
gkwal
Newbie
Posts: 25
|
|
find x in ^(1/4) equation
« on: Jul 16th, 2007, 9:39pm » |
Quote Modify
|
(x+27)^(1/4) + (55-x)^1/4 =4; x=?
|
|
IP Logged |
|
|
|
ThudnBlunder
wu::riddles Moderator Uberpuzzler
The dewdrop slides into the shining Sea
Gender:
Posts: 4489
|
|
Re: find x in ^(1/4) equation
« Reply #1 on: Jul 17th, 2007, 9:04am » |
Quote Modify
|
x = 54 or -26
|
|
IP Logged |
THE MEEK SHALL INHERIT THE EARTH.....................................................................er, if that's all right with the rest of you.
|
|
|
Barukh
Uberpuzzler
Gender:
Posts: 2276
|
|
Re: find x in ^(1/4) equation
« Reply #2 on: Jul 17th, 2007, 9:24am » |
Quote Modify
|
u + v = 4, u4 + v4 = 82.
|
|
IP Logged |
|
|
|
srn437
Newbie
the dark lord rises again....
Posts: 1
|
|
Re: find x in ^(1/4) equation
« Reply #3 on: Sep 6th, 2007, 8:24pm » |
Quote Modify
|
V=1 u=3 or vice verca. Now here's one for you people to answer. (1-x)^1/3+(x-3)^1/3=1 Here's a hint, cubing it leads to extraneous solutions like x=2.
|
|
IP Logged |
|
|
|
mikedagr8
Uberpuzzler
A rich man is one who is content; not wealthy.
Gender:
Posts: 1105
|
|
Re: find x in ^(1/4) equation
« Reply #4 on: Sep 7th, 2007, 3:18am » |
Quote Modify
|
on Sep 6th, 2007, 8:24pm, srn347 wrote:V=1 u=3 or vice verca. Now here's one for you people to answer. (1-x)^1/3+(x-3)^1/3=1 Here's a hint, cubing it leads to extraneous solutions like x=2. |
| You need to spread it out more. Do you mean (1-x)1/3 + (x-3)1/3 = 1? Becuase if not, what do you mean, I want to get this correct. It doesn't seem to be an answer. I seem to get 4=1 when I cube it. If I graph it won't intersect. I've also been able to make 4-x = x. This is not possible to do, if it is using the equation I stated above.
|
« Last Edit: Sep 7th, 2007, 4:04am by mikedagr8 » |
IP Logged |
"It's not that I'm correct, it's that you're just not correct, and so; I am right." - M.P.E.
|
|
|
srn437
Newbie
the dark lord rises again....
Posts: 1
|
|
Re: find x in ^(1/4) equation
« Reply #5 on: Sep 8th, 2007, 8:12am » |
Quote Modify
|
It is what I mean. If you cube it , simplify, cube again, simplify agai, and apply quadratics, you get x=2, which doesn't work for the real cube root, but perhaps for the complex. http://en.wikipedia.org/wiki/Invalid_proof
|
|
IP Logged |
|
|
|
|