因式分解
(b1−b2)(c1d2−c2d1)−(d1−d2)(a1b2−a2b1)(b_1-b_2)(c_1d_2-c_2d_1)-(d_1-d_2)(a_1b_2-a_2b_1)(b1−b2)(c1d2−c2d1)−(d1−d2)(a1b2−a2b1)