Question
Download Solution PDFComprehension
Let f(x) = [x2] where [.] is the greatest integer function.
\(\int_{\sqrt{2}}^{2} f(x) dx\) is equal to ?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFCalculation:
Given,
The function is \( f(x) = \lfloor x^2 \rfloor \).
We are tasked with finding the value of \( \int_{\sqrt{2}}^{2} f(x) dx \).
We can break the integral into two parts as follows:
\( \int_{\sqrt{2}}^{2} f(x) dx = \int_{\sqrt{2}}^{\sqrt{3}} 2 dx + \int_{\sqrt{3}}^{2} 3 dx \)
For the range \( \sqrt{2} \leq x \leq \sqrt{3} \), \( \lfloor x^2 \rfloor = 2 \). So the first part of the integral is:
\( \int_{\sqrt{2}}^{\sqrt{3}} 2 dx = 2 \times (\sqrt{3} - \sqrt{2}) \)
For the range \( \sqrt{3} \leq x \leq 2 \), \( \lfloor x^2 \rfloor = 3 \). So the second part of the integral is:
\( \int_{\sqrt{3}}^{2} 3 dx = 3 \times (2 - \sqrt{3}) \)
Now, we calculate the values:
\( 2 \times (\sqrt{3} - \sqrt{2}) = 2\sqrt{3} - 2\sqrt{2} \)
\( 3 \times (2 - \sqrt{3}) = 6 - 3\sqrt{3} \)
Combining the two parts:
\( 2\sqrt{3} - 2\sqrt{2} + 6 - 3\sqrt{3} = 6 - 2\sqrt{2} - \sqrt{3} \)
Hence, the correct answer is Option 1.
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