n はよ皚
n顶よ皚A璝Τ n顶よ皚Bㄏ眔 AB = BA = In嘿 B琌 Aはよ皚A-1 ボ
• 讽 n顶よ皚A ㄣΤはよ皚玥嘿 A琌癴よ皚 玥
• よ皚A Τはよ皚璶兵ン琌 det(A) ≮ 0
n
顶よ皚はよ皚顶よ皚 A = det(A) = = ad-bc
△ A-1 =
n
顶よ皚はよ皚
顶よ皚 A =
1.det(A) : 癸莱じ籔A常妓顶︽Α
det(A) =
2.緇 Aij 琌盢材 i 籔材 j ︽じ埃┮眔顶
︽Ατ (-1)i+jAij 碞嘿 aij 緇
△ A-1 = [A( j , i )緇]3x3