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Find integer matrices, not multiples of each other, such that A² = B² = I and AB = BA.

User Anuj Arora
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Final answer:

To find integer matrices A and B such that A² = B² = I and AB = BA, we can use the concept of eigenvectors and eigenvalues.

Step-by-step explanation:

To find integer matrices A and B such that A² = B² = I and AB = BA, we can use the concept of eigenvectors and eigenvalues. Let's assume that A and B are 2x2 matrices. Since A² = B² = I, the eigenvalues of A and B must be 1 and -1. The eigenvectors corresponding to the eigenvalue 1 can be any non-zero vector; let's choose (1, 0). The eigenvectors corresponding to the eigenvalue -1 can be any vector orthogonal to (1, 0); let's choose (0, 1). Therefore, the matrix A can be [1 0; 0 -1] and the matrix B can be [1 0; 0 1]. These matrices satisfy A² = B² = I and AB = BA.

User Marc Buurke
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