Let A be an n x n matrix such that A^3 = On

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In summary, the notation "A^3" means that the matrix A is being multiplied by itself three times, also known as the third power of A. The "On" in the statement refers to the zero matrix, also known as the matrix filled with all zeros. It is denoted by the symbol "O" with a subscript of "n" to indicate that it is an n x n matrix. This is possible when the matrix A has at least one eigenvalue of 0. When a matrix is multiplied by itself, the eigenvalues are raised to the power of the exponent. So, if A has an eigenvalue of 0, then A^3 will also have an eigenvalue of 0, resulting in the
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squenshl
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I have a problem.
Let A be an n x n matrix such that A^3 = On (On is a n x n zero matrix). Show that the only possible eigenvalue for A is 0.
 
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An eigenvalue lambda must satisfy

Ax = lambda x

for some nonzero vector x.

Now multiply both sides of the above equation on the left by A, twice, and substitute lambda x in place of Ax where appropriate.

What is the resulting equation, and what does it imply about lambda?
 

FAQ: Let A be an n x n matrix such that A^3 = On

What does the notation "A^3" mean in the given statement?

The notation "A^3" means that the matrix A is being multiplied by itself three times, also known as the third power of A.

What does the "On" mean in the given statement?

The "On" in the statement refers to the zero matrix, also known as the matrix filled with all zeros. It is denoted by the symbol "O" with a subscript of "n" to indicate that it is an n x n matrix.

How can a matrix multiplied by itself three times result in the zero matrix?

This is possible when the matrix A has at least one eigenvalue of 0. When a matrix is multiplied by itself, the eigenvalues are raised to the power of the exponent. So, if A has an eigenvalue of 0, then A^3 will also have an eigenvalue of 0, resulting in the zero matrix.

Is there any other way for A^3 to equal the zero matrix?

Yes, it is also possible for A to have a singular value decomposition (SVD) with at least one singular value equal to 0. In this case, when A is multiplied by itself three times, the singular values will also be raised to the power of the exponent, resulting in the zero matrix.

What are some real-world applications of this property of matrices?

This property is often used in fields such as physics and engineering to solve systems of equations and model physical processes. It can also be used in computer graphics to rotate objects or in cryptography to encrypt and decrypt messages.

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