Срочно упростите выражение

(√6 + √3) *√12 - 2√6 * √3 =
= √(6²*2 ) + √36 - 2√(3²*2) =
= 6√2 + 6 - 6√2 = 6

$( \frac{6}{y^2-9} + \frac{1}{3-y} ) * \frac{y^2 + 6y + 9}{5} = \\ \\ = ( \frac{6}{(y-3)(y+3)} - \frac{1}{y-3} ) * \frac{y^2+2*3y+3^2}{5} = \\ \\ = \frac{6-(y+3)}{(y-3)(y+3)} * \frac{(y+3)^2}{5} = \frac{6-y-3}{(y-3)(y+3)} * \frac{(y+3)^2}{5}= \\ \\ = \frac{-(y-3)*(y+3)^2}{(y-3)(y+3)*5} = \frac{-(y+3)}{5} = - \frac{y+3}{5} = \\ \\ = - \frac{1}{5} *(y+3) = -0.2(y+3) = -0.2y -0.6$