Inegalitate proprie cu radicali intr-un triunghi.

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Virgil Nicula
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Inegalitate proprie cu radicali intr-un triunghi.

Post by Virgil Nicula »

Sa se arate ca in orice triunghi \( ABC \) exista inegalitatea \( \sum\sqrt {\frac {b + c - a}{a}} + 2\sum\frac {a}{b + c}\ \ge \ 6. \)
Last edited by Virgil Nicula on Wed Jan 28, 2009 4:20 pm, edited 2 times in total.
Marius Mainea
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Post by Marius Mainea »

Aplicand ineg \( M_g\ge M_h \)

\( LHS=\sum {\sqrt{\frac{b+c-a}{a}}+2\sum{\frac{a}{b+c}}\ge\sum {\frac{2}{\frac{a}{b+c-a}+1}}+2\sum{\frac{a}{b+c}}=2\sum{\frac{b+c-a}{b+c}}+2\sum{\frac{a}{b+c}}=6=RHS \)
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