If A is 5 by 5. then ABBA = zero matrix gives 25 equations for the 25 entries in B. Show
Chapter 5, Problem 5.2.44(choose chapter or problem)
If A is 5 by 5. then ABBA = zero matrix gives 25 equations for the 25 entries in B. Show that the 25 by 25 matrix is singular by noticing a simple nonzero solution B.
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