NDA 2025
- Exam
- NDA
- Year
- 2025
- Subject
- Mathematics
- Chapter
- Application of Derivatives
NDA 2025 · Mathematics · Application of Derivatives
Consider the following for the two (02) items that follow: Let the...
Consider the following for the two (02) items that follow:
Let the function .
Consider the following statements:
I. is an increasing function.
II. has local maximum at .
Which of the statements given above is/are correct?
Let the function .
Consider the following statements:
I. is an increasing function.
II. has local maximum at .
Which of the statements given above is/are correct?
Options
- AI only
- BII only
- CBoth I and II
- DNeither I nor II
Correct answer
D. Neither I nor II
Step-by-step solution
Given .
Differentiating with respect to , we get .
For , , which means is strictly decreasing in .
For , , which means is strictly increasing in .
Since is not increasing on its entire domain, Statement I is incorrect.
To find local extrema, we set , which gives .
The second derivative is .
Since , has a local minimum at , not a local maximum.
Thus, Statement II is also incorrect.
Both statements are incorrect.
Answer: Neither I nor II
Differentiating with respect to , we get .
For , , which means is strictly decreasing in .
For , , which means is strictly increasing in .
Since is not increasing on its entire domain, Statement I is incorrect.
To find local extrema, we set , which gives .
The second derivative is .
Since , has a local minimum at , not a local maximum.
Thus, Statement II is also incorrect.
Both statements are incorrect.
Answer: Neither I nor II