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#1 2008-03-03 22:51:58
- gyanshrestha
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- Registered: 2007-11-06
- Posts: 41
solve
solve for x
autually the power is 2/3 and 1/3.
soryy for inconvinieces
Last edited by gyanshrestha (2008-03-03 23:00:51)
http://gyan.talkacademy.com.np
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#2 2008-03-04 01:00:34
- JaneFairfax
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- Registered: 2007-02-23
- Posts: 6,868
Re: solve
Your equation is
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#3 2008-03-04 02:08:25
- gyanshrestha
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- Registered: 2007-11-06
- Posts: 41
Re: solve
yes and thanks JaneFairFax
actually i am confusing on giving the exponets.
can any one solve? please.
http://gyan.talkacademy.com.np
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#4 2008-03-04 02:08:26
- Identity
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- Registered: 2007-04-18
- Posts: 934
Re: solve
From this we know
and must both be rational numbers, since the sum of two irrational numbers is irrational.So the cube root of two rational numbers add to 3.
Listing them out, we find that
, for instance, seems a likely candidate. But , so it cannot be solved.I haven't proven this because I'm sleepy but I think that there exists no number such that the sum of it's cube root and its reciprocal's cube root can give 3.
i.e. no solution (not QED)
Last edited by Identity (2008-03-04 02:09:19)
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#5 2008-03-04 02:11:02
- gyanshrestha
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- Registered: 2007-11-06
- Posts: 41
Re: solve
then can we solve the equation in terms of a?
http://gyan.talkacademy.com.np
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#6 2008-03-04 02:19:19
- Identity
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- Registered: 2007-04-18
- Posts: 934
Re: solve
Of course! I didn't notice that two irrational numbers could be added like that... in class my teacher actually told us that two irrational numbers summed to another irrational number. 
Last edited by Identity (2008-03-04 02:21:04)
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#7 2008-03-04 02:19:42
- JaneFairfax
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- Registered: 2007-02-23
- Posts: 6,868
Re: solve
since the sum of two irrational numbers is irrational.
The way to solve the equation is to let
so you havePS: Sorry, Identity. I deleted my previous post and reposted this one but you replied in the meantime. 
Last edited by JaneFairfax (2008-03-04 02:22:30)
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#8 2008-03-04 02:22:31
- gyanshrestha
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- Registered: 2007-11-06
- Posts: 41
Re: solve
actually the equation was given by a student of my friend and has aslo has solution that is 2a/sqrt5.
how does it come?
http://gyan.talkacademy.com.np
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#9 2008-03-10 22:52:28
- shree
- Guest
Re: solve
i posted its answer two or three days ago and it was successfully posted but now its gone.
how could this be
#10 2008-03-11 03:28:52
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: solve
That's probably because you posted while the servers were being switched. We unavoidably lost about a day's posts around then.
There was an announcement that that would happen though.
Why did the vector cross the road?
It wanted to be normal.
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