Cho các số thực a,b,c thỏa mãn \(0\le a,b,c\le1\)và \(a+b+c\ge2\).CMR:
\(ab\left(a+1\right)+bc\left(b+1\right)+ca\left(c+1\right)\ge2\)
Cho a, b, c > 0 và abc = 1. CMR:
\(\frac{a^3}{\left(1+b\right)\left(1+c\right)}+\frac{b^3}{\left(1+c\right)\left(1+a\right)}+\frac{c^3}{\left(1+a\right)\left(1+b\right)}\ge\frac{3}{4}\)
Cho a,b,c là các số thực không âm và n ≥ log23 - 1. Chứng minh rằng :
\(\left(\frac{a}{b+c}\right)^n+\left(\frac{b}{c+a}\right)^n+\left(\frac{c}{a+b}\right)^n+\frac{\left(2^{n+1}-3\right)abc}{2^{n-3}\left(a+b\right)\left(b+c\right)\left(c+a\right)}\ge2\)
Cho a,b,c > 0. Cmr :
\(\dfrac{1}{a\left(1+b\right)}+\dfrac{1}{b\left(1+c\right)}+\dfrac{1}{c\left(1+a\right)}\ge\dfrac{3}{1+abc}\)
Cho a,b,c đôi một khác nhau. CMR: \(\frac{\left(a+b\right)^2}{\left(a-b\right)^2}+\frac{\left(b+c\right)^2}{\left(b-c\right)^2}+\frac{\left(c+a\right)^2}{\left(c-a\right)^2}\ge2\)
Cho a, b, c > 0 và a + b + c = 3. CMR: \(\frac{a^3}{\left(a+1\right)\left(b+1\right)}+\frac{b^3}{\left(b+1\right)\left(c+1\right)}+\frac{c^3}{\left(c+1\right)\left(a+1\right)}\ge\frac{3}{4}\)
a;b;c>0 thỏa mãn abc=1. CMR:
\(\frac{a}{\left(a+1\right)\left(b+1\right)}+\frac{b}{\left(b+1\right)\left(c+1\right)}+\frac{c}{\left(a+1\right)\left(b+1\right)}\ge\frac{3}{4}\)
\(\left(1+\frac{a}{b}\right)\left(1+\frac{b}{c}\right)\left(1+\frac{c}{a}\right)\ge2\left(1+\frac{a+b+c}{\sqrt[3]{abc}}\right)\)
cho a,b,c.>0 thoả mãn ab+bc+ac=1. CMR
\(\left(1+a\right)^2\left(1+b\right)^2\left(1+c\right)^2+\left(1-a\right)^2\left(1-b\right)^2\left(1-c\right)^2\ge8\sqrt{3}abc\)