Competition problem — Algebra — Maths Olympiad Prep

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Algebra Difficulty 6.2 National olympiad Prove it

75. Given that $a, b, c$ are positive numbers, and $a+b+c=1$ , prove: $\frac{a-b c}{a+b c}+\frac{b-c a}{b+c a}+\frac{c-a b}{c+a b} \leqslant \frac{3}{2}$ .

Solution

None

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None

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