silemus.

40Powers of a diagonal matrix

Compute A10\displaystyle A^{10} for A=[2003]\displaystyle A = \begin{bmatrix}2 & 0\\0 & 3\end{bmatrix}.

For a diagonal matrix, raising it to a power just raises each diagonal entry to that power—no entries mix. So A^10 = diag(2^10, 3^10) = diag(1024, 59049). Check: A² = diag(4,9) matches 2² and 3².

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