If A is an invertible matrix with det(A) = 5, what is the determinant of the inverse matrix A^(-1)?
Answer and explanation
Correct answer: C. 1/5
- Step 1: For any invertible matrix, det(A^(-1)) = 1 / det(A). Step 2. Since det(A) = 5, det(A^(-1)) = 1/5. Answer: 1/5. Why not the others: 5 is the original determinant; -5 negates the determinant; 25 squares det(A).
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