JEE Advanced 2013Paper 1
- Exam
- JEE Advanced
- Year
- 2013
- Paper
- Paper 1
- Subject
- Mathematics
- Chapter
- Differentiation
JEE Advanced 2013 · Paper 1 · Mathematics · Differentiation
Let f (x) = x π x , x > 0 . Then for all natural numbers n , f ^ ′...
Let f \left(\text{x}\right) = \text{x} \text\sin \pi \text{x}, . Then for all natural numbers vanishes at
Options
- AA unique point in the interval
- BA unique point in the interval
- CA unique point in the interval (n, n + 1)
- DTwo points in the interval (n, n + 1)
Correct answer
B. A unique point in the interval
Step-by-step solution
As vanishes,
{\text{f}}^{′} \left(\text{x}\right) = \text\sin \pi \text{x} + \pi x cos \pi \text{x} = 0
\text\tan \pi \text{x} = - \pi \text{x}
We will draw the graph of tan \pix & - \pi x.
And their intersection points will be the points, where vanishes.