X is a 3x3 matrix (spaces used for separation) 1 3 9 1 4 16 1 5 25 I want to know X( X - 12I) where I is the 3x3 identity matrix. Can someone explain/show?
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Originally Posted by acu04385 X is a 3x3 matrix (spaces used for separation) 1 3 9 1 4 16 1 5 25 I want to know X( X - 12I) where I is the 3x3 identity matrix. Can someone explain/show? As it is written, it says multiple the identity matrix by 12, subtract X from the 12I and then multiple X by the that matrix.
Many thanks i was confusing myself with the relationship IA = AI = A
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