Q = \(x^2\) + 2y² + 4\(x-4y\) + 11

 Q = (\(x^2\) + 4\(x\) + 4) + (2y² - 4y + 2) + 5

Q = (\(x+2\))² + 2.(y - 1)² + 5

Vì (\(x+2\))² ≥ 0 ∀ \(x\); 2(y  -1)² ≥ 0 ∀ y ⇒ Q ≥ 5 > 0 (đpcm)

\(Q=x^2+2y^2+4x-4y+11\)

\(=x^2+4x+4+2y^2-4y+2+5\)

\(=\left(x+2\right)^2+2\left(y^2-2y+1\right)+5\)

\(=\left(x+2\right)^2+2\left(y-1\right)^2+5>=5>0\forall x,y\)

It takes us 15 minutes to cycle to school everyday

->we spend 15 minutes to cycle to school everyday.

Trả lời: We spend 15 minutes cyling to school everyday.

My favorite leisure activity is playing video games. Many people going to say that was bad but hear me out, everything has its own bad and good ya know? Yes, before I play video games, my reaction times and aim are so bad that I can't even play badminton properly 💀. Badminton needs fast reaction times and good aim. After I try playing video games, my aim is increase and my reaction times reduce from over 400ms down to only about 130ms. Insane right? But buddy, you need to remember that don't play too much or you will be lose your sight and your scores badly, I recommend you play video games less than 2 hours and starting to find other activity that is good for your health