Math Riddle | 17 Jul 2009

Go4Expert Founder
17Jul2009,21:47   #1
shabbir's Avatar
A bit tricky and interesting as well

x+y+z=0
x^3+y^3+z^3=3
x^5+y^5+z^5=15

x^2+y^2+z^2=?

^ = Power of
Go4Expert Member
18Jul2009,04:36   #2
rik625's Avatar
Hey...

x^2+y^2+z^2 =1

Im i right???
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18Jul2009,05:42   #3
xpi0t0s's Avatar
It'd better not be as simple as that...after several hours and sheets of paper I'm just about to give up on solving it with simultaneous equations...
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18Jul2009,06:15   #4
xpi0t0s's Avatar
However that did give me a useful inequality...so I'm going to register a guess, that x^2+y^2+z^2 is an integer and is precisely 6. Just running another, more accurate, test but it'll take a while to produce results.
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18Jul2009,07:19   #5
shabbir's Avatar
Quote:
Originally Posted by xpi0t0s View Post
However that did give me a useful inequality...so I'm going to register a guess, that x^2+y^2+z^2 is an integer and is precisely 6. Just running another, more accurate, test but it'll take a while to produce results.
Yes that is the right Answer

I have the values of x,y,z as well if you want to.
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18Jul2009,07:48   #6
naimish's Avatar
@ xpi0t0s, Congrs Buddy
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18Jul2009,12:56   #7
SaswatPadhi's Avatar
Of course X^2+y^2+z^2 can be real even if x, y, z are all complex. But, I'm just curious .. Do these equations have any real solutions ??
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18Jul2009,12:59   #8
SaswatPadhi's Avatar
I wonder why I keep getting 60 as the answer.
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18Jul2009,13:02   #9
shabbir's Avatar
The answer is 6 and X=3, y=-2 and Z=-1
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18Jul2009,13:06   #10
SaswatPadhi's Avatar
But 3^3 + (-2)^3 + (-1) ^3 = 27-8-1 = 18 ??

Further, 3^2 + (-2)^2 + (-1)^2 = 9 + 4 + 1 = 14 ?!