Concursul Matefbc editia a 2-a problema 5
Posted: Sun Dec 06, 2009 8:02 pm
Fie \( a, b, c, d \) patru numere reale pozitive astfel incat \( a\leq b \leq c \leq d \) cu \( abcd=1 \). Atunci are loc inegalitatea:
\( (a+1)(d+1)\geq 3+\frac{3}{4d^3} \).
\( (a+1)(d+1)\geq 3+\frac{3}{4d^3} \).