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f(x) = {{:(x^(2)sin'1/x, if x ne 0),(...

`f(x) = {{:(x^(2)sin'1/x, if x ne 0),(0, if x = 0):}` at `x = 0`.

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To determine the differentiability of the function \( f(x) \) defined as: \[ f(x) = \begin{cases} x^2 \sin\left(\frac{1}{x}\right) & \text{if } x \neq 0 \\ 0 & \text{if } x = 0 \end{cases} \] at \( x = 0 \), we need to find both the left-hand derivative and the right-hand derivative at that point. ### Step 1: Find the Left-Hand Derivative The left-hand derivative at \( x = 0 \) is given by: \[ f'_{-}(0) = \lim_{h \to 0^-} \frac{f(0 + h) - f(0)}{h} \] Substituting \( f(0) = 0 \): \[ f'_{-}(0) = \lim_{h \to 0^-} \frac{f(h)}{h} = \lim_{h \to 0^-} \frac{h^2 \sin\left(\frac{1}{h}\right)}{h} \] This simplifies to: \[ f'_{-}(0) = \lim_{h \to 0^-} h \sin\left(\frac{1}{h}\right) \] Since \( \sin\left(\frac{1}{h}\right) \) oscillates between -1 and 1, we have: \[ -h \leq h \sin\left(\frac{1}{h}\right) \leq h \] As \( h \to 0 \), both bounds approach 0. By the Squeeze Theorem: \[ f'_{-}(0) = 0 \] ### Step 2: Find the Right-Hand Derivative The right-hand derivative at \( x = 0 \) is given by: \[ f'_{+}(0) = \lim_{h \to 0^+} \frac{f(0 + h) - f(0)}{h} \] Again substituting \( f(0) = 0 \): \[ f'_{+}(0) = \lim_{h \to 0^+} \frac{f(h)}{h} = \lim_{h \to 0^+} \frac{h^2 \sin\left(\frac{1}{h}\right)}{h} \] This simplifies to: \[ f'_{+}(0) = \lim_{h \to 0^+} h \sin\left(\frac{1}{h}\right) \] Similar to the left-hand case, since \( \sin\left(\frac{1}{h}\right) \) oscillates between -1 and 1: \[ -h \leq h \sin\left(\frac{1}{h}\right) \leq h \] As \( h \to 0 \), both bounds approach 0. By the Squeeze Theorem: \[ f'_{+}(0) = 0 \] ### Step 3: Conclusion Since both the left-hand and right-hand derivatives at \( x = 0 \) are equal: \[ f'_{-}(0) = f'_{+}(0) = 0 \] We conclude that \( f(x) \) is differentiable at \( x = 0 \) and: \[ f'(0) = 0 \]

To determine the differentiability of the function \( f(x) \) defined as: \[ f(x) = \begin{cases} x^2 \sin\left(\frac{1}{x}\right) & \text{if } x \neq 0 \\ 0 & \text{if } x = 0 \end{cases} ...
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