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Let $A$ be a $n \times n$ matrix, $n$ even, with even diagonal elements and all other elements odd integers. Prove that $\det(A)\neq 0$. Can anyone give me a hint? Thank you.

Seirios
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user62138
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2 Answers2

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Hint: Compute the determinant of $A$ reduced modulo $2$.

Seirios
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1

The determinant is an odd integer then.

Marc Palm
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