Cho \(M_1=\left(\sqrt{a}+\sqrt{b}-\sqrt{c}\right)^2\left(\sqrt{b}+\sqrt{c}-\sqrt{a}\right)^2\left(\sqrt{c}+\sqrt{a}-\sqrt{b}\right)^2\)
\(M_2=\left(\sqrt[4]{a}+\sqrt[4]{b}-\sqrt[4]{c}\right)^4\left(\sqrt[4]{b}+\sqrt[4]{c}-\sqrt[4]{a}\right)^4\left(\sqrt[4]{c}+\sqrt[4]{a}-\sqrt[4]{b}\right)^4\)
\(...\)
\(M_n=\left(\sqrt[2^n]{a}+\sqrt[2^n]{b}-\sqrt[2^n]{c}\right)^{2^n}\left(\sqrt[2^n]{b}+\sqrt[2^n]{c}-\sqrt[2^n]{a}\right)^{2^n}\left(\sqrt[2^n]{c}+\sqrt[2^n]{a}-\sqrt[2^n]{b}\right)^{2^n}\)
Với \(n\inℕ^∗\). CMR: \(\left(a+b-c\right)\left(b+c-a\right)\left(c+a-b\right)\le M_1\le M_2\le...\le M_n\le abc\)
áp dụng BĐT bunhia
a, cho \(2x^2+3y^2\le5\)
cmr \(-5\le2x+3y\le5\)
b, cho a, b >c>0 cmr
\(\sqrt{\left(a+c\right)\left(b+c\right)}+\sqrt{\left(a-c\right)\left(b-c\right)}\le\sqrt{ab}\)
c, cmr \(a^2+b^2+c^2\ge ab+bc+ac\)
d, \(\sqrt{\left(a+c\right)^2+\left(b+d\right)^2}\le\sqrt{a^2+b^2}+\sqrt{c^2+d^2}\)
lm đc bài nào cũng đc cả nhớ bunhia nha
1) Cho a,b,c>0 tm a+b+c=3. Cmr \(\frac{1}{2+a^2+b^2}+\frac{1}{2+b^2+c^2}+\frac{1}{2+c^2+a^2}\le\frac{3}{4}\)
2) Cho a,b,c>0 tm a^2+b^2+c^2 bé hơn hoặc bằng abc. Cmr \(\frac{a}{a^2+bc}+\frac{b}{b^2+ca}+\frac{c}{c^2+ab}\le\frac{1}{2}\)
3) Cho a,b,c>0 tm a+b+c<=3. Cmr \(\frac{ab}{\sqrt{3+c}}+\frac{bc}{\sqrt{3+a}}+\frac{ca}{\sqrt{3+b}}\le\frac{3}{2}\)
4) Cho a,b,c>0 tm a+b+c=2. Cmr \(\frac{a}{\sqrt{4a+3bc}}+\frac{b}{\sqrt{4b+3ca}}+\frac{c}{\sqrt{4c+3ab}}\le1\)
5) Cho a,b,c>0. Cmr \(\sqrt{\frac{a^3}{5a^2+\left(b+c\right)^2}}+\sqrt{\frac{b^3}{5b^2+\left(c+a\right)^2}}+\sqrt{\frac{c^3}{5c^2+\left(a+b\right)^2}}\le\sqrt{\frac{a+b+c}{3}}\)
6) Cho a,b,c>0. Cmr \(\frac{a^2}{\left(2a+b\right)\left(2a+c\right)}+\frac{b^2}{\left(2b+a\right)\left(2b+c\right)}+\frac{c^2}{\left(2c+a\right)\left(2c+b\right)}\le\frac{1}{3}\)
Giúp mình với nhé các bạn
Cho \(a,b,c\) \(\ge0\) và \(a+b+c=\sqrt{5}\)
CMR: \(\left|\left(a^2-b^2\right)\left(b^2-c^2\right)\left(c^2-a^2\right)\right|\le\sqrt{5}\)
Cho a;b;c >0 thỏa mãn a+b+c=5 và \(\sqrt{a}+\sqrt{b}+\sqrt{c}=3\). CMR:
\(\frac{\sqrt{a}}{a+2}+\frac{\sqrt{b}}{b+2}+\frac{\sqrt{c}}{c+2}=\frac{4}{\sqrt{\left(a+2\right)\left(b+2\right)\left(c+2\right)}}\)
Cho a, b,c,d >0. CMR
\(\sqrt{\left(a^2+b^2\right)\left(b^2+c^2\right)}+\sqrt{\left(a^2+d^2\right)\left(b^2+d^2\right)}>\left(a+b\right)\left(c+d\right)\)
Cho a, b, c là các số dương thỏa mãn điều kiện a+b+c+\(\sqrt{2abc}=2\)
CMR \(\sqrt{a\left(2-b\right)\left(2-c\right)}+\sqrt{b\left(2-c\right)\left(2-a\right)}+\sqrt{c\left(2-a\right)\left(2-b\right)}=\sqrt{8}+\sqrt{abc}\)
giúp mik vs nhé cảm ơn rất nhìu
Cho x,y,z dương tuỳ ý. CMR
\(\sqrt{a\left(b+1\right)}+\sqrt{b\left(c+1\right)}+\sqrt{c\left(a+1\right)}\le\frac{3}{2}\sqrt{\left(a+1\right)\left(b+1\right)\left(c+1\right)}\)
Cho a, b, c là các số dương . CMR:
\(\frac{a\left(b+2c\right)}{\sqrt{3b^2+6c^2}}+\frac{b\left(c+2a\right)}{\sqrt{3c^2+6a^2}}+\frac{c\left(a+2b\right)}{\sqrt{3a^2+6b^2}}\le a+b+c\)