Suma de patrate e patru

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alex2008
Leibniz
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Suma de patrate e patru

Post by alex2008 »

Fie \( a,b,c,d \) trei numere reale satisfacand constrangerea \( a^2+b^2+c^2+d^2=4. \) Sa se demonstreze ca \( a^3+b^3+c^3+d^3\le 8. \)
. A snake that slithers on the ground can only dream of flying through the air.
Marius Mainea
Gauss
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Post by Marius Mainea »

\( \sum a^3\le 2\sum a^2=8 \)
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