Question

выполните сложение и вычитание дробей 3/3-y - y/y^2-9

Answer 1

$\displaystyle \frac{3}{3-y}- \frac{y}{y^2-9} = \frac{3}{3-y}+ \frac{y}{(3-y)(3+y)} = \frac{3(3+y)+y}{(3-y)(3+y)} = \frac{9+4y}{9-y^2}$