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If D is a 3x3 determinant with value Delta, and A1, B1, C1 (etc.) denote the cofactors of its entries, then the value of the determinant formed by all these cofactors equals:

1. Delta
2. Delta²
3. Delta³
4. 0

Correct answer: Delta²

Solution

For a 3x3 determinant, the determinant of cofactors is Delta^(n-1) = Delta².

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