Cho a,b t/m: \(\left\{{}\begin{matrix}a^3-a^2+a-5=0\\b^3-2b^2+2b+4=0\end{matrix}\right.\)

Tính \(a+b?\)

Tìm min với \(x\ge\dfrac{-1}{2}\)

\(A=\sqrt{2x^2+5x+2}+2\sqrt{x+3}-2x\)

Tìm min với \(x\ge\dfrac{-1}{2}\)

\(A=\sqrt{2x^2+5x+2}+2\sqrt{x+3}-2x\)

Cho a,b t/m: \(\left\{{}\begin{matrix}a^3-a^2+a-5=0\\b^3-2b^2+2b+4=0\end{matrix}\right.\)

Tính \(a+b?\)

 Cho a,b,c>0 tm: abc=1

CM: \(a+b+c\ge\dfrac{ab+1}{b+1}+\dfrac{bc+1}{c+1}+\dfrac{ca+1}{a+1}\)

Cho \(A=\dfrac{1}{\sqrt{1}+\sqrt{2}}+\dfrac{1}{\sqrt{3}+\sqrt{4}}+...+\dfrac{1}{\sqrt{99}+\sqrt{100}}\)

CMR: \(A\notin Z\)

Cho \(x=\dfrac{2}{2\sqrt[3]{2}+2+\sqrt[3]{4}};y=\dfrac{6}{2\sqrt[3]{2}-2+\sqrt[3]{4}}\)

Tính \(A=xy^3-x^3y\)