NDA 2025
- Exam
- NDA
- Year
- 2025
- Subject
- Mathematics
- Chapter
- Application of Derivatives
NDA 2025 · Mathematics · Application of Derivatives
For the following two (02) items: Consider the function f(x) = 1 -...
For the following two (02) items:
Consider the function .
The function has
Consider the function .
The function has
Options
- Aa minimum at
- Ba maximum at
- Cneither maximum nor minimum at
- Dno extremum
Correct answer
B. a maximum at
Step-by-step solution
Given
Differentiating with respect to :
For , . Thus, is strictly increasing.
For , . Thus, is strictly decreasing.
Since changes sign from positive to negative as passes through , has a local maximum at .
Alternatively, for all real .
for all .
Hence, has a maximum at .
Answer: a maximum at
Differentiating with respect to :
For , . Thus, is strictly increasing.
For , . Thus, is strictly decreasing.
Since changes sign from positive to negative as passes through , has a local maximum at .
Alternatively, for all real .
for all .
Hence, has a maximum at .
Answer: a maximum at