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Question #41370
The Question
Let , , and be three vectors parameterized by . Let , , and . For such that , let be the reciprocal system of vectors for . If is the continuous extension of the function over the interval , find the sum of all values of at which attains a local extremum.
Options
- A.
3
- B.
9
- C.
6
- D.
12
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Bridge
Practice problems that bridge the gap between foundational theory and advanced practical application.
Concepts Behind This Question
First Derivative Test Trap|Vector Triple Product Expansion|Reciprocal System of Vectors
Why This Question Is Tricky
Common Mistakes
This question tests the student's ability to handle scalar triple products of reciprocal systems and the critical absolute value trap in vector magnitudes.
The trap is set by the square root of a squared scalar triple product, , which simplifies to , not just .
Students who blindly apply the first derivative test to the algebraic polynomial without the absolute value will only find the local maximum at , missing the non-differentiable local minima at the roots and where the vectors become coplanar.
Quick Facts About This Question
Question Information
| Subject | Mathematics |
| Chapter | Application of Derivatives - Class 12 |
| Concept | First Derivative Test Trap |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |