12 13 D= 22 23.列标 33 行标 阶行列式的计算 13 lI 12 (1)沙路法D=2423A2a2 31 31 D=a123+a12a2331+a13213 112332 12·2133 1322u3131 32 21 22 11 12 a a a a a a − − − + + + . − a11a23a32 − a12a21a33 − a13a22a31 (1)沙路法 三阶行列式的计算 D = a11a22a33 + a12a23a31 + a13a21a32 31 32 33 21 22 23 11 12 13 a a a a a a a a a D = .列标 行标 31 32 33 21 22 23 11 12 13 a a a a a a a a a D =