3/(x+3) + 3/(x²-3x) + 2x/(9 - x²)=
= 3/(x+3) + 3/(х(x - 3)) - 2x/((х - 3)(х + 3)) =
= 3·х·(х - 3) + 3·(х + 3) - 2х·х =
= 3х² - 9х + 3х + 9 - 2х² =
= х² - 6х + 9 =
= (х -3)²
если это 1/16a^2+1/6ab+1/9b^2 = 0
Смотри...............,........