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Question #41492

Difficulty: 8/10 | 🟢 Free

The Question

Evaluate the definite integral: I=∫02π6cos⁡x−6sin⁡x+53+2sin⁡x+2cos⁡x dxI = \int_{0}^{2\pi} \frac{6\cos x - 6\sin x + 5}{3 + 2\sin x + 2\cos x} \, dx

Options

  • A.

    10π10\pi

  • B.

    00

  • C.

    5π5\pi

  • D.

    12π12\pi

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

Substitution (Change of Variable)|Logarithmic Integration via Trig Manipulation|Extraneous Solution Rejection

Why This Question Is Tricky

Common Mistakes

The question tests the student's ability to recognize derivative patterns in rational trigonometric integrals to avoid brutal substitutions.

A common trap is applying the Weierstrass substitution t=tan⁡(x/2)t = \tan(x/2) to the entire integral, which converts it into a complex rational algebraic function requiring logarithmic integration via partial fractions.

Because t=tan⁡(x/2)t = \tan(x/2) is discontinuous at x=πx = \pi, integrating blindly from the lower limit t=0t=0 to the upper limit t=0t=0 yields an extraneous result of 00.

This 'Lethal Collision' with the fundamental theorem of calculus punishes algorithmic substitution without domain analysis, a hallmark of JEE Advanced Extraneous Solution Rejection traps.

Quick Facts About This Question

Question Information

SubjectMathematics
ChapterIntegrals - Class 12
ConceptSubstitution (Change of Variable)
Difficulty8
Cognitive Load7
Target Solve Time160 sec
AccessFree