- Exam
- JEE Main
- Year
- 2022
- Date
- 25 July
- Shift
- Evening Shift
- Subject
- Mathematics
- Chapter
- Definite Integration
JEE Main 2022 · 25 July · Evening Shift · Mathematics · Definite Integration
Let [t] denote the greatest integer less than or equal to t . Then...
Options
- A\dfrac{52\left(1 - e\right)}{e}
- B
- C\dfrac{52\left(2 + e\right)}{e}
- D
Correct answer
B.
Step-by-step solution
Given,
Now let and
Now checking periodicity of \left[sin\pix\right]0 < x < 1 ⇒ \left[sin\pix\right] = 01 < x < 2 ⇒ \left[sin\pix\right] = - 1 periodic with period 2
So,
Now checking periodicity of \left[\cos 2\pix\right]0 < x < \dfrac{1}{4} ⇒ \left[\cos 2\pix\right] = 0\dfrac{1}{4} < x < \dfrac{1}{2} ⇒ \left[\cos 2\pix\right] = - 1\dfrac{1}{2} < x < \dfrac{3}{4} ⇒ \left[\cos 2\pix\right] = - 1\dfrac{3}{4} < x < 1 ⇒ \left[\cos 2\pix\right] = 0 has periodicity of
So, {I}_{2} = 104\left({∫}_{0}^{}{e}^{0}dx + {∫}_{}^{}{e}^{- 1}dx + {∫}_{}^{1}{e}^{0}dx\right)</p><p>⇒ {I}_{2} = 104\left(\dfrac{1}{4} + \dfrac{1}{e} \times \dfrac{1}{2} + \dfrac{1}{4}\right)⇒ {I}_{2} = 52 + \dfrac{52}{e}{I}_{1} + {I}_{2} = \dfrac{52}{e}{∫}_{- 3}^{101}\left(\left[sin\pix\right] + {e}^{\left[\cos 2\pix\right]}\right)dx = \dfrac{52}{e}