If A is a square matrix such that A squared equals A, then A is called what?

B. Idempotent matrix — By definition, a square matrix is called idempotent if the square of the matrix is equal to the matrix itself. This is a standard classification in matrix algebra.

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$If A is a square matrix such that A^{2} = A, then A is called what?$

A. $Symmetric matrix$
B. $Idempotent matrix$
C. $Involutory matrix$
D. $Nilpotent matrix$

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Correct answer: B — $Idempotent matrix$

Solution

By definition, a square matrix A is called idempotent if A^{2} = A . This is a standard classification in matrix algebra.

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If A is a square matrix such that A2=A, then A is called what?

Solution

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More Matrices & Determinants practice questions

$If A is a square matrix such that A^{2} = A, then A is called what?$