什么是行列式的按行展开或者按列展开？它是怎么展开的？比如按第1行展开或者按第2列展开？ 计算行列式时按行展开和按列展开效果一样吗
\u4ec0\u4e48\u662f\u884c\u5217\u5f0f\u7684\u6309\u884c\u5c55\u5f00\u6216\u8005\u6309\u5217\u5c55\u5f00\u8bbe\u884c\u5217\u5f0f\uff1aD=|a11 a12 ... a1n|
a21 a22 ... a2n
..........................
............... aij ...........
.........................
an1 an2 ... ann
\u5219 \u6309\u884c\u5c55\u5f00 D=a11A11+a12A12+...+a1jA1j+...+a1nA1n
=ai1Ai1+ai2Ai2+...+aijAij+...+ainAin
=an1An1+an2An2+...+anjAnj+...+annAnn
\u6309\u5217\u5c55\u5f00 D=a11A11+a21A21+...+ai1Ai1+...+an1An1
=a1jA1j+a2jA2j+...+aijAij+...+anjAnj
=a1nA1n+a2nA2n+...+ainAin+...+annAnn
\u3010\u82e5\u6709\u5177\u4f53\u4f8b\u5b50\uff0c\u4e5f\u53ef\u4ee5\u5177\u4f53\u300a\u5c55\u300b\u7ed9\u4f60\u77a7\u77a7\u3011
\u6548\u679c\u4e00\u6837\u7684
\u6240\u4ee5\u4e00\u4e2a\u77e9\u9635\u548c\u5176\u8f6c\u7f6e\u77e9\u9635\u7684\u884c\u5217\u5f0f\u5fc5\u7136\u76f8\u540c
a(1,1)*M(1,1)+a(1,2)*M(1,2)+...+a(1,n)*M(1,n)
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绛旓細璁 |A|=|aij| 鏄痭闃琛屽垪寮 |A| 鎸夌1琛屽睍寮, 灏辨槸绗1琛岀殑鏁颁箻瀹冨搴旂殑浠ｆ暟浣欏瓙寮 涔嬪拰.鍗 |A| = a11A11+a12A12+...+a1nA1n
