1. Cho a,b,c thỏa mãn $a^2+b^2+c^2 >0$
CMR
$\sum \frac{a^2-bc}{4a^2+4b^2+c^2}\geq 0$
2. Cho a,b,c thực thỏa mãn a+b+c=0
CMR
$\sum \frac{a^2+2a}{2a^2+1}\geq 0$
Edited by lenadal, 08-07-2017 - 16:58.
$\sum \frac{a^2-bc}{4a^2+4b^2+c^2}\geq 0$
Started By lenadal, 08-07-2017 - 16:19
1 user(s) are reading this topic
0 members, 1 guests, 0 anonymous users
