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 Author Comment/Response Kai 07/10/13 3:01pm Hi all For exams I am studying matrices and I am using Mathematica for verifying my results. But I have a little trouble here because my minors result matrix looks kinda different. For example I used this video: [URL]https://www.khanacademy.org/math/algebra/algebra-matrices/inverting_matrices/v/inverting-3x3-part-1--calculating-matrix-of-minors-and-cofactor-matrix[/URL] {{-1, -2, 2}, {2, 1, 1}, {3, 4, 5}} If I look at the minors Mathematica gives this result: {{3, -5, -4}, {2, -11, -18}, {5, 7, 1}} where I expect like in the video {{1, 7, 5}, {-18, -11, 2}, {-4, -5, 3}} So it is flipped somehow. But if I take a look at the second video: [URL]https://www.khanacademy.org/math/algebra/algebra-matrices/inverting_matrices/v/inverting-3x3-part-2--determinant-and-adjugate-of-a-matrix[/URL] The inverse of the matrix looks all the same both in video and mathematica {{1/23, 18/23, -(4/23)}, {-(7/23), -(11/23), 5/23}, {5/23, -(2/23), 3/ 23}} Could someone explain this to me? I don't get it :-( Thanks URL: ,

 Subject (listing for 'Matrices & Minors') Author Date Posted Matrices & Minors Kai 07/10/13 3:01pm Re: Matrices & Minors Peter Pein 07/11/13 2:15pm
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