[線代] 一題作業 想不出來

看板Math作者 (雲出無心)時間12年前 (2012/03/11 00:04), 編輯推噓1(1推 0噓 1→)
留言2則, 2人參與, 最新討論串1/1
題目如下: Suppose thAT A is a square matrix satisfying A^3 + 2A^2 + 3A + I = 0 Find the inverses of A and (A+I) -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.113.247.134
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03/11 00:11, , 1F
I = -(A^3 + 2A^2 +3A) = A (-A^2 - 2A -3)
03/11 00:11, 1F
推
03/11 00:12, , 2F
A(-A^2 - 2A - 3I ) = I, (A+I)(A^2+A+2I) = I
03/11 00:12, 2F
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文章代碼(AID): #1FMtkA7z (Math)