Sao dài thế :v

\(1+\left(-2\right)^2-\left(-1\right)^0=1+4-1=4\)

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

\(\left(x+2y\right)^2=x^2+4xy+4y^2\)

We are going to move to a new apartment next month
 

B

1. walks

2. do / get
 

\(\Rightarrow x^2>1\Rightarrow x>1\) hoặc \(x< -1\)

1C

2B

\(V\)_{xe máy} = 36 km/h

\(V\)_{ô tô} = 54 km/h