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x,y>0 x+y=1 tìm min,max $\sqrt{x^{2014}+1} + \sqrt{y^{2014}+1}$

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#1
ZzZzZzZzZ

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x,y>0, x+y=1 tìm min,max

$\sqrt{x^{2014}+1} + \sqrt{y^{2014}+1}$



#2
Kaito Kuroba

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x,y>0, x+y=1 tìm min,max

$\sqrt{x^{2014}+1} + \sqrt{y^{2014}+1}$

 

 

theo mincopki ta có:

$P\ge \sqrt{4+(\sum x^{1007})} $
mặt khác ta lại có:
$\sum x^{1007}\ge \frac{(x+y)^{1007}}{2^{1006}}$

Do đó $P\ge \sqrt{4+\frac{1}{2^{2012}}}$
$"="\Leftrightarrow $$x=y=\frac{1}{2}$


Edited by Kaito Kuroba, 06-03-2014 - 12:10.


#3
Ispectorgadget

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