\(P=x^2+2y^2+2xy-6x-8y+2024\)
\(P=x^2+y^2+y^2+2xy-6x-6y-2y+2024\)
\(P=\left(x^2+2xy+y^2\right)-\left(6x+6y\right)+9+y^2-2y+1+2014\)
\(P=\left(x+y\right)^2-2\left(x+y\right)3+3^2+\left(y^2-2y+1\right)+2014\)
\(P=\left(x+y-3\right)^2+\left(y-1\right)^2+2014\)
\(P\ge2014\forall x;y\)
Dấu "=" xảy ra \(\Leftrightarrow\hept{\begin{cases}x+y-3=0\\y-1=0\end{cases}\Leftrightarrow\hept{\begin{cases}x=2\\y=1\end{cases}}}\)
Vậy.....