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1. let a be a square matrix with entries in c such that a2023 is diagonaliz- able. show that a2024 is also diagonalizable

User Shawndumas
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1 Answer

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Final answer:

Given that matrix A to the power of 2023 is diagonalizable, it follows that A to the power of 2024 is also diagonalizable by expressing it as a product of A with its 2023rd power and using the properties of diagonalizable matrices and matrix multiplication.

Step-by-step explanation:

The question is about determining the diagonalizability of a square matrix A raised to the power of 2024, given that A to the power of 2023 is diagonalizable.

If a matrix A is diagonalizable, there exists a diagonal matrix D and an invertible matrix P such that A = PDP-1. Since A2023 is diagonalizable, let's say A2023 = PDP-1, then A2024 can be written as A·A2023 = A·PDP-1 = PDA-1P-1.

If we assume that D is a diagonal matrix with the eigenvalues of A, then P would consist of the corresponding eigenvectors.

Because matrix multiplication is associative, we can group P with DA-1 to form another diagonal matrix D’, such that A2024 = PD’P-1, showing that A2024 is also diagonalizable.

User Imre Raudsepp
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