cho 3 so a,b,c duong chung minh:
\(\frac{1}{a^2+bc}+\frac{1}{b^2+ac}+\frac{1}{c^2+ab}\le\frac{a+b+c}{2abc}\)
cho a+b+c=1.chung minh:\(\frac{ab}{c+1}+\frac{bc}{a+1}+\frac{ac}{b+1}\le\frac{1}{4}\)
cho ca so a,b,c duong thoa man ab+bc+ca =1 chung minh \(P=\frac{2a}{\sqrt{1+a^2}}+\frac{b}{\sqrt{1+b^2}}+\frac{c}{\sqrt{1+c^2}}\le\frac{1}{4}\)
cho 3 so a,b,c duong va a+b+c=1 CM\(\frac{ab}{c+1}+\frac{bc}{a+1}+\frac{ac}{b+1}\le\frac{1}{4}\)
voi a+b+c=1. chung minh:\(\frac{ab}{c+1}+\frac{bc}{a+1}+\frac{ac}{a+1}<\frac{1}{4}\)
cho cac so a,b,c duong thoa man ab+bc+ca=1 chung minh : \(p=\frac{2a}{\sqrt{1+a^2}}+\frac{b}{\sqrt{1+b^2}}+\frac{c}{\sqrt{1+c^2}}\)
cho a,b,c la ba so thuc duong thoa man dieu kien a+b+c=1
chung minh rang P=\(\sqrt{\frac{ab}{c+ab}}+\sqrt{\frac{bc}{a+bc}}+\sqrt{\frac{ca}{b+ca}}\le\frac{3}{2}\)
Cho a,b,c là các số thực dương thỏa mãn a+b+c=3abc. Chứng minh rằng :
\(\left(\frac{1}{a}+\frac{1}{b}+\frac{1}{c}\right)^2\left[\frac{a^4}{\left(ab+1\right)\left(ac+1\right)}+\frac{b^4}{\left(bc+1\right)\left(ab+1\right)}+\frac{c^4}{\left(ca+1\right)\left(bc+1\right)}\right]\ge\frac{27}{4}\)
Cho 3 số thực dương a,b,c thoả mãn a+b+=1. Chứng minh rằng \(\frac{a-bc}{a+bc}+\frac{b-ac}{b+ac}+\frac{c-ab}{c+ab}\le\frac{3}{4}\)