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#1 2007-12-29 19:14:10
- Identity
- Member
- Registered: 2007-04-18
- Posts: 934
minimum
Find the minimum value of (x+y)(y+z) if xyz(x+y+z) =1. I tried substituting out a variable but it's gotten very messy verry quickly.. thanks (please try not to use calculus)
edit: x, y, and z are positive real numbers
Last edited by Identity (2007-12-29 19:23:59)
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#2 2007-12-29 21:40:04
- JaneFairfax
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- Registered: 2007-02-23
- Posts: 6,868
Re: minimum
Dont you mean find the minimum value of
? It seems odd to want to find an inequality involving a non-symmetrical expression without being allowed to use calculus.I can suggest trying the substitution
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