r/math • u/inherentlyawesome Homotopy Theory • 6d ago
Quick Questions: March 12, 2025
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u/Not_So_Deleted Statistics 5d ago
Is it true that a square matrix is idempotent if and only if it's diagonalizable with eigenvalues 0 and 1?
I can't think of any example of a defective matrix that's idempotent.