x^2 - x - 6 < 0 ==> (x + 2)(x - 3) < 0 ==> -2 < x < 3 0 < x - m < 9 ==> m < x < 9 + m(1) m < -2, 且 9 + m > 3 ==> m < - 2, 且 m > - 6 ==> -6 < m < -2(2) 9 + m <= - 2 或 9 + m >= 3 ==> m <= -11 或 m >= -6