Question

Phân tích đa thức thành nhân tử 

x^2-y^2-2y-1

Answer 1

\(x^2-y^2-2y-1\)

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

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

\(=\left(x-y-1\right)\left(x+y+1\right)\)

Answer 2

( x-y-1)

Answer 3

\(x^2-y^2-2y-1\)

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

\(=\left(x+y+1\right)\left(x-y-1\right)\)

=.= hok tốt!!