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#1 2012-09-23 21:59:31
- hammana
- Member
- Registered: 2012-03-02
- Posts: 48
inequation a/b+b/c+c/d+d/a>=4
If a, b, c, d are 4 positive numbers, show that
a/b+b/c+c/d+d/a>=4
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#2 2012-09-24 00:52:05
- anonimnystefy
- Real Member
- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: inequation a/b+b/c+c/d+d/a>=4
Hi hammana
Have you heard of the AM-GM inequality?
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#3 2012-09-24 04:35:30
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: inequation a/b+b/c+c/d+d/a>=4
Hi;
Have you left out some constraint on this problem?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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