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f(x)={{:(|x|cos\ 1/x, if x ne 0),(0, if ...

`f(x)={{:(|x|cos\ 1/x, if x ne 0),(0, if x =0):}` at `x = 0` .

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To determine whether the function \( f(x) \) is continuous at \( x = 0 \), we need to check the following: 1. **Value of the function at \( x = 0 \)**: \[ f(0) = 0 \] 2. **Left-hand limit as \( x \) approaches 0**: \[ \lim_{x \to 0^-} f(x) = \lim_{x \to 0^-} |x| \cos\left(\frac{1}{x}\right) \] Since \( x \) is approaching 0 from the left, we have \( |x| = -x \). Thus, we can rewrite the limit as: \[ \lim_{h \to 0^+} h \cos\left(\frac{1}{-h}\right) = \lim_{h \to 0^+} h \cos\left(-\frac{1}{h}\right) = \lim_{h \to 0^+} h \cos\left(\frac{1}{h}\right) \] 3. **Evaluating the limit**: The cosine function oscillates between -1 and 1, so we can bound the limit: \[ -h \leq h \cos\left(\frac{1}{h}\right) \leq h \] As \( h \to 0^+ \), both bounds approach 0: \[ \lim_{h \to 0^+} -h = 0 \quad \text{and} \quad \lim_{h \to 0^+} h = 0 \] By the Squeeze Theorem: \[ \lim_{h \to 0^+} h \cos\left(\frac{1}{h}\right) = 0 \] 4. **Conclusion about the left-hand limit**: Therefore, we have: \[ \lim_{x \to 0^-} f(x) = 0 \] 5. **Right-hand limit as \( x \) approaches 0**: \[ \lim_{x \to 0^+} f(x) = \lim_{x \to 0^+} |x| \cos\left(\frac{1}{x}\right) = \lim_{h \to 0^+} h \cos\left(\frac{1}{h}\right) \] Following the same reasoning as above, we find: \[ \lim_{h \to 0^+} h \cos\left(\frac{1}{h}\right) = 0 \] 6. **Conclusion about the right-hand limit**: Therefore, we have: \[ \lim_{x \to 0^+} f(x) = 0 \] 7. **Final check for continuity**: Since both the left-hand limit and the right-hand limit at \( x = 0 \) are equal to the value of the function at that point: \[ \lim_{x \to 0} f(x) = f(0) = 0 \] We conclude that \( f(x) \) is continuous at \( x = 0 \). ### Summary: The function \( f(x) \) is continuous at \( x = 0 \).

To determine whether the function \( f(x) \) is continuous at \( x = 0 \), we need to check the following: 1. **Value of the function at \( x = 0 \)**: \[ f(0) = 0 \] 2. **Left-hand limit as \( x \) approaches 0**: ...
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