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Question #40417

Difficulty: 8/10 | 🟢 Free

The Question

Find the sum of all real values of xx in the interval [0,1000][0, 1000] that satisfy the equation: sin⁡−1(sin⁡x∘)−cos⁡−1(cos⁡x∘)=−π6\sin^{-1}(\sin x^\circ) - \cos^{-1}(\cos x^\circ) = -\frac{\pi}{6}

Options

  • A.

    2445

  • B.

    2325

  • C.

    1620

  • D.

    1395

Check Your Answer

Correct Answer

Step-by-Step Solution

Explanation

How the Examiner Thinks

Specialist

Targeted practice for niche, high-difficulty concepts that frequently appear in JEE Advanced exams.

Concepts Behind This Question

Radian-Degree Conversion Identity|Algebraic-Trigonometric Graphical Mapping|Principal Value Branch Boundaries

Why This Question Is Tricky

Common Mistakes

This question tests the student's ability to map algebraic degree inputs to the principal value branches of inverse trigonometric functions.

The primary trap lies in assuming a false periodicity (e.g., 180 instead of 360) or failing to correctly identify the piecewise definitions of sin⁡−1(sin⁡θ)\sin^{-1}(\sin \theta) and cos⁡−1(cos⁡θ)\cos^{-1}(\cos \theta) across different quadrants.

A common mistake is assuming sin⁡−1(sin⁡x∘)=πx180\sin^{-1}(\sin x^\circ) = \frac{\pi x}{180} universally, which yields no solutions, or finding only the first branch solution (x=105x=105) and missing the fourth quadrant branch (x=345x=345).

Another trap is assuming the combination has a period of 180, leading to the incorrect sum of 2325.

Quick Facts About This Question

Question Information

SubjectMathematics
ChapterTrigonometric Functions - Class 11
ConceptRadian-Degree Conversion Identity
Difficulty8
Cognitive Load7
Target Solve Time160 sec
AccessFree