NDA 2024
- Exam
- NDA
- Year
- 2024
- Subject
- Mathematics
- Chapter
- Application of Derivatives
NDA 2024 · Mathematics · Application of Derivatives
Let f(x)=(x)/( x) ;(x > 1) Consider the following statements: 1. f^...
Let
Consider the following statements:
1. attains local minimum value at f(x)e
Options
- A1 and 2 only
- B2 and 3 only
- C1 and 3 only
- D1,2 and 3
Correct answer
D. 1,2 and 3
Step-by-step solution
\Rightarrow \quad f^{\prime \prime}(e)=\frac{1-2+2}{e \times 1}=\frac{1}{e}( > 0)\Rightarrowf^{\prime \prime}(e) > 0f(x)x=e\Rightarrowx=ef(x)x=ef(e)=\frac{e}{\ln e}=e\Rightarrow$ Statement (3) is correct.
Hence, Statements (1), (2) and (3) are correct.