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Topic: range of function (Read 968 times) |
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cool_joh
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range of function
« on: Dec 17th, 2008, 5:25pm » |
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Find the set of possible values of the expression f(x,y,z)={ (xyz) / (xy+yz+zx) } for positive integers x,y,z. Here {a} is the fractional part of a.
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Eigenray
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Re: range of function
« Reply #1 on: Dec 17th, 2008, 9:36pm » |
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x = a(b-1), y = z = 2a(b-1)2
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cool_joh
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Re: range of function
« Reply #2 on: Dec 18th, 2008, 5:44am » |
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Very nice hint, Eigenray! Another hint: f(kx,ky,kz)={kf(x,y,z)} (prove this first)
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