Question

Làm tính chưa

( x mũ 2 - y mũ 2 + 6x + 9 ) : ( x + y + 3 )

Answer 1

\(\frac{x^2-y^2+6x+9}{x+y+3}=\frac{\left(x+3\right)^2-y^2}{x+y+3}=\frac{\left(x+3-y\right)\left(x+3+y\right)}{x+y+3}=x-y+3\)