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Question #40309
The Question
Let be a invertible real matrix with , and let be its adjugate matrix. For any index sets , let denote the submatrix of a matrix formed by taking the rows indexed by and columns indexed by , both in increasing order. Let and . If and , where denotes the complement of in , what is the value of ?
Options
- A.
-40
- B.
40
- C.
-56
- D.
56
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Monster
Ultra-high difficulty questions designed to test your limit, stamina, and deep conceptual understanding.
Concepts Behind This Question
Set Complement Boundaries|Row/Column Exchange Parity|Determinant Product Rule
Why This Question Is Tricky
Common Mistakes
This question tests the advanced application of Jacobi's Theorem for adjugate minors, specifically targeting the 'Row/Column Exchange Parity' and 'Set Complement Boundaries' traps.
Students commonly make two lethal errors here: (1) ignoring the permutation parity shift caused by reordering the index boundaries, which leads to the incorrect sign (Option B), and (2) failing to transpose the complementary sets (using instead of ), which collapses the algebraic structure and leads to evaluating the wrong submatrix (Options C and D).
Quick Facts About This Question
Question Information
| Subject | Mathematics |
| Chapter | Sets - Class 11 |
| Concept | Set Complement Boundaries |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |