perplexus.info :: Just Math : A simple inequality

A simple inequality (Posted on 2014-12-31)

Given:
x>0, y>0, x+y=1

Prove that
(1 + 1/x)(1 + 1/y) ≥ 9.

No Solution Yet Submitted by Ady TZIDON

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Solution

| Comment 3 of 4 |

y = 1-x

(1+1/x)(1+1/y) >= 9 becomes (2x-1)^2 >= 0

Obvious.

Posted by Bractals on 2014-12-31 13:31:00

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