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Consider the following in respect of the...

Consider the following in respect of the function
`f(x)={{:(2+x","xge0),(2-x","xlt0):}`
1. `lim_(x to 1) f(x)` does not exist.
2. f(x) is differentiable at x=0
3. f(x) is continuous at x=0
Which of the above statements is /aer correct?

A

1 only

B

3 olny

C

2 and 3 only

D

1 and 3 only

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The correct Answer is:
To solve the problem, we will analyze the function \( f(x) \) defined as follows: \[ f(x) = \begin{cases} 2 + x & \text{if } x \geq 0 \\ 2 - x & \text{if } x < 0 \end{cases} \] We need to evaluate the three statements regarding the function: 1. \( \lim_{x \to 1} f(x) \) does not exist. 2. \( f(x) \) is differentiable at \( x = 0 \). 3. \( f(x) \) is continuous at \( x = 0 \). ### Step 1: Evaluate the limit as \( x \to 1 \) Since \( 1 \geq 0 \), we will use the first case of the function: \[ f(1) = 2 + 1 = 3 \] Now, we find the limit: \[ \lim_{x \to 1} f(x) = f(1) = 3 \] **Conclusion for Statement 1**: The limit exists, hence the statement is **incorrect**. ### Step 2: Check continuity at \( x = 0 \) To check continuity at \( x = 0 \), we need to evaluate: - \( f(0) \) - \( \lim_{x \to 0^-} f(x) \) (left-hand limit) - \( \lim_{x \to 0^+} f(x) \) (right-hand limit) Calculating \( f(0) \): \[ f(0) = 2 + 0 = 2 \] Calculating the left-hand limit as \( x \to 0 \) (using \( f(x) = 2 - x \) for \( x < 0 \)): \[ \lim_{x \to 0^-} f(x) = \lim_{x \to 0^-} (2 - x) = 2 - 0 = 2 \] Calculating the right-hand limit as \( x \to 0 \) (using \( f(x) = 2 + x \) for \( x \geq 0 \)): \[ \lim_{x \to 0^+} f(x) = \lim_{x \to 0^+} (2 + x) = 2 + 0 = 2 \] Since both limits equal \( f(0) \): \[ \lim_{x \to 0} f(x) = f(0) = 2 \] **Conclusion for Statement 3**: The function is continuous at \( x = 0 \), hence this statement is **correct**. ### Step 3: Check differentiability at \( x = 0 \) To check differentiability at \( x = 0 \), we need to find the left-hand and right-hand derivatives. **Left-hand derivative**: \[ \lim_{h \to 0^-} \frac{f(0 + h) - f(0)}{h} = \lim_{h \to 0^-} \frac{(2 - h) - 2}{h} = \lim_{h \to 0^-} \frac{-h}{h} = -1 \] **Right-hand derivative**: \[ \lim_{h \to 0^+} \frac{f(0 + h) - f(0)}{h} = \lim_{h \to 0^+} \frac{(2 + h) - 2}{h} = \lim_{h \to 0^+} \frac{h}{h} = 1 \] Since the left-hand derivative \(-1\) is not equal to the right-hand derivative \(1\), the function is not differentiable at \( x = 0 \). **Conclusion for Statement 2**: The function is not differentiable at \( x = 0\), hence this statement is **incorrect**. ### Final Conclusion - Statement 1: Incorrect - Statement 2: Incorrect - Statement 3: Correct Thus, the only correct statement is **3**.

To solve the problem, we will analyze the function \( f(x) \) defined as follows: \[ f(x) = \begin{cases} 2 + x & \text{if } x \geq 0 \\ 2 - x & \text{if } x < 0 \end{cases} ...
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