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Let f(x)={{:("x-|x|",","x ne0),(1,","x=0...

Let `f(x)={{:("x-|x|",","x ne0),(1,","x=0):}`then

A

`lim_(xto0+) f(x)=1`

B

`lim_(x to 0-) f(x)=0`

C

`lim_(x to 0+) f(x) ne lim_(x to 0-) f(x)`

D

`lim_(x to 0+) f(x)` does not exist

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the function defined as: \[ f(x) = \begin{cases} x - |x| & \text{if } x \neq 0 \\ 1 & \text{if } x = 0 \end{cases} \] We will find the left-hand limit and the right-hand limit as \( x \) approaches 0. ### Step 1: Determine the left-hand limit as \( x \) approaches 0 For \( x < 0 \): - The expression for \( |x| \) is \( -x \). - Therefore, \( f(x) = x - (-x) = x + x = 2x \). Now we calculate the left-hand limit: \[ \lim_{x \to 0^-} f(x) = \lim_{x \to 0^-} 2x = 2 \cdot 0 = 0. \] ### Step 2: Determine the right-hand limit as \( x \) approaches 0 For \( x > 0 \): - The expression for \( |x| \) is \( x \). - Therefore, \( f(x) = x - x = 0 \). Now we calculate the right-hand limit: \[ \lim_{x \to 0^+} f(x) = \lim_{x \to 0^+} 0 = 0. \] ### Step 3: Compare the left-hand limit and right-hand limit From the calculations: - Left-hand limit: \( \lim_{x \to 0^-} f(x) = 0 \) - Right-hand limit: \( \lim_{x \to 0^+} f(x) = 0 \) Since both limits are equal, we can conclude: \[ \lim_{x \to 0} f(x) = 0. \] ### Step 4: Evaluate the function at \( x = 0 \) According to the definition of the function: \[ f(0) = 1. \] ### Conclusion The limit as \( x \) approaches 0 exists and is equal to 0, but the value of the function at \( x = 0 \) is 1. Therefore, the function is not continuous at \( x = 0 \). ### Summary of Results - \( \lim_{x \to 0^-} f(x) = 0 \) - \( \lim_{x \to 0^+} f(x) = 0 \) - \( f(0) = 1 \)
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