Question
Download Solution PDFComprehension
Let f(x) = [x2] where [.] is the greatest integer function.
What \(\int_{\sqrt{2}}^{\sqrt{3}} f(x) dx\) equal to?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFCalculation:
Given,
The function is \( f(x) = \left\lfloor x^2 \right\rfloor \), where \( \left\lfloor x^2 \right\rfloor \) is the greatest integer function.
We are tasked with finding:
\( \int_{\frac{\sqrt{3}}{2}}^{\sqrt{3}} \left\lfloor x^2 \right\rfloor \, dx \)
Decomposing the integral based on the function:
For \\(\frac{\sqrt{3}}{2} \leq x < 1 \), x2 lies between \(\frac{3}{4} \) and 1, so \(\left\lfloor x^2 \right\rfloor = 0 \). Therefore,
\( \int_{\frac{\sqrt{3}}{2}}^1 0 \, dx = 0 \)
For\( 1 \leq x < \sqrt{2} \), x2 lies between 1 and 2, so \(\left\lfloor x^2 \right\rfloor = 1 .\) Therefore,
\( \int_1^{\sqrt{2}} 1 \, dx = \sqrt{2} - 1 \)
For \(\sqrt{2} \leq x < \sqrt{3} \), x2 lies between 2 and 3, so \(\left\lfloor x^2 \right\rfloor = 2\) . Therefore,
\( \int_{\sqrt{2}}^{\sqrt{3}} 2 \, dx = 2(\sqrt{3} - \sqrt{2}) \)
Summing up all the results:
\( \int_{\frac{\sqrt{3}}{2}}^{\sqrt{3}} \left\lfloor x^2 \right\rfloor \, dx = 0 + (\sqrt{2} - 1) + 2(\sqrt{3} - \sqrt{2}) \)
= \( 2(\sqrt{3} - \sqrt{2}) \).
Hence, the correct answer is Option 2.
Last updated on Jul 8, 2025
->UPSC NDA Application Correction Window is open from 7th July to 9th July 2025.
->UPSC had extended the UPSC NDA 2 Registration Date till 20th June 2025.
-> A total of 406 vacancies have been announced for NDA 2 Exam 2025.
->The NDA exam date 2025 has been announced. The written examination will be held on 14th September 2025.
-> The selection process for the NDA exam includes a Written Exam and SSB Interview.
-> Candidates who get successful selection under UPSC NDA will get a salary range between Rs. 15,600 to Rs. 39,100.
-> Candidates must go through the NDA previous year question paper. Attempting the NDA mock test is also essential.