MCQMediumJEE 2024Limits

JEE Mathematics 2024 Question with Solution

Evaluate the limit limxπ/2[(1xπ2)0π/2cos(1t3)dt]\lim_{x \to \pi/2} \left[\left(\frac{1}{x} - \frac{\pi}{2}\right) * \int_{0}^{\pi/2} \cos\left(\frac{1}{t^3}\right) \, dt\right], which is equal to:

  • A

    3π/83\pi/8

  • B

    3π2/43\pi^2/4

  • C

    3π2/83\pi^2/8

  • D

    3π/43\pi/4

Answer

Correct answer:C

Step-by-step solution

Standard Method

Given: The limit expression is

limxπ/2[(1xπ2)0π/2cos(1t3)dt]\lim_{x \to \pi/2} \left[\left(\frac{1}{x} - \frac{\pi}{2}\right) * \int_{0}^{\pi/2} \cos\left(\frac{1}{t^3}\right) \, dt\right]

Find: Its value.

From the solution, using L'Hôpital's Rule and the Fundamental Theorem of Calculus, the expression simplifies to 3π2/83\pi^2/8 as xπ/2x \to \pi/2.

Therefore, the correct option is C.

Extracted Conclusion

The solution explicitly states: using L'Hôpital's Rule and the Fundamental Theorem of Calculus, the given expression simplifies to 3π2/83\pi^2/8.

Hence the required limit is 3π2/83\pi^2/8.

Common mistakes

  • Treating the integral as dependent on xx exactly as written here is a common mistake. The provided printed expression appears ambiguous, so the answer must be grounded in the solution rather than guessed from a faulty direct reading.

  • Applying L'Hôpital's Rule without first identifying the indeterminate form is incorrect. One should confirm the limiting structure before differentiating numerator and denominator.

  • Ignoring the conclusion from the extracted solution and mapping the answer only from option text can be risky when the question statement is ambiguously scraped. Use the solution.

Practice more Limits questions

Get unlimited AI-adaptive practice, mastery tracking, and an AI tutor that explains every step — free to start.

Related questions