Question

giúp vs ạ:>>

Answer 1

giúp mik vs gấp lắm:<<

Answer 2

\(P=x^2+2y^2+2xy-4x-10y+21=\left[x^2+2x\left(y-2\right)+\left(y-2\right)^2\right]+\left(y^2-6y+9\right)+8=\left(x+y-2\right)^2+\left(y-3\right)^2+8\ge8\)

\(minP=8\Leftrightarrow\)\(\left\{{}\begin{matrix}x=-1\\y=3\end{matrix}\right.\)

Answer 3

bạn ơi y^2 chứ có phải 2y^2 đâu