NDA 2025
- Exam
- NDA
- Year
- 2025
- Subject
- Mathematics
- Chapter
- Continuity and Differentiability
NDA 2025 · Mathematics · Continuity and Differentiability
For the following two (02) items: Let the function f(x) = |x - 3| +...
For the following two (02) items:
Let the function be defined on the interval .
Consider the following statements:
I. The function is differentiable at .
II. The function is differentiable at .
Which of the statements given above is/are correct?
Let the function be defined on the interval .
Consider the following statements:
I. The function is differentiable at .
II. The function is differentiable 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
The given function is defined on .
We can redefine the function by removing the absolute value signs in different intervals:
\begin{cases} -(x - 3) - (x - 4), & 0 \le x < 3 \\ (x - 3) - (x - 4), & 3 \le x < 4 \\ (x - 3) + (x - 4), & 4 \le x \le 5 \end{cases}<br><br>Simplifying this, we get:<br><br>$f(x) = $\begin{cases} 7 - 2x, & 0 \le x < 3 \\ 1, & 3 \le x < 4 \\ 2x - 7, & 4 \le x \le 5 \end{cases}
Differentiating with respect to in the open intervals:
\begin{cases} -2, & 0 < x < 3 \\ 0, & 3 < x < 4 \\ 2, & 4 < x < 5 \end{cases}$x = 3= -2= 0 f(x)x = 3x = 4= 0= 2 f(x)x = 4$.
Therefore, neither statement I nor statement II is correct.
Answer: Neither I nor II
We can redefine the function by removing the absolute value signs in different intervals:
\begin{cases} -(x - 3) - (x - 4), & 0 \le x < 3 \\ (x - 3) - (x - 4), & 3 \le x < 4 \\ (x - 3) + (x - 4), & 4 \le x \le 5 \end{cases}<br><br>Simplifying this, we get:<br><br>$f(x) = $\begin{cases} 7 - 2x, & 0 \le x < 3 \\ 1, & 3 \le x < 4 \\ 2x - 7, & 4 \le x \le 5 \end{cases}
Differentiating with respect to in the open intervals:
\begin{cases} -2, & 0 < x < 3 \\ 0, & 3 < x < 4 \\ 2, & 4 < x < 5 \end{cases}$x = 3= -2= 0 f(x)x = 3x = 4= 0= 2 f(x)x = 4$.
Therefore, neither statement I nor statement II is correct.
Answer: Neither I nor II