X 2 27 x 3 x 9 0 July 8, 2019 16 32 64 128 27 x 5 * 9 x 3 x 2 45 0 X mũ 3 9 x mũ 2 27 x 19 0 X mũ 3 trừ 9 x mũ 2 27 x 35 0 (x ^ 3 - 27)/(x ^ 2 - 9)