Definition of an Identity MatrixDate: 08/09/99 at 12:00:59 From: noor Subject: Identity Matrix Can someone please tell me what is the definition of an identity matrix? Which of the following would be an identity matrix? -1 2 1 -3 -2 2 3 -4 -5 7 3 -4 -5 6 Date: 08/10/99 at 01:28:11 From: Doctor Rob Subject: Re: Identity Matrix None of these is an identity matrix. An identity matrix must be a square. All the off-diagonal entries are zero. Finally, the entries on the main diagonal are all ones. For example, [1 0 0] [0 1 0] [0 0 1] - Doctor Rob, The Math Forum http://mathforum.org/dr.math/ |
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