Question

Сократите дробь x^3+4x^2−9x−36
                            (x−3)(x+ 4)

Answer 1

$frac{x^3+4x^2-9x-36}{(x-3)(x+ 4)} = frac{left(x-3right) left(x^2+7x+12right)}{(x-3)(x+ 4)} =$

$= frac{ left(x^2+7x+12right)}{(x+ 4)} = frac{left(x+4right) left(x+3right)}{(x+ 4)} = x+3$