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Check monotonocity at following points f...

Check monotonocity at following points for
`f(x) =x^(3) -3x +1` at `x= -1,2`.

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To check the monotonicity of the function \( f(x) = x^3 - 3x + 1 \) at the points \( x = -1 \) and \( x = 2 \), we will follow these steps: ### Step 1: Find the derivative of the function. The first step is to differentiate the function \( f(x) \). \[ f'(x) = \frac{d}{dx}(x^3 - 3x + 1) = 3x^2 - 3 \] ### Step 2: Factor the derivative. Next, we can factor the derivative to make it easier to analyze. \[ f'(x) = 3(x^2 - 1) = 3(x - 1)(x + 1) \] ### Step 3: Check the derivative at \( x = -1 \). Now, we will evaluate the derivative at \( x = -1 \). \[ f'(-1) = 3((-1)^2 - 1) = 3(1 - 1) = 3 \cdot 0 = 0 \] ### Step 4: Analyze the result at \( x = -1 \). Since \( f'(-1) = 0 \), we cannot determine whether the function is increasing or decreasing at this point. Therefore, we conclude that the function is neither increasing nor decreasing at \( x = -1 \). ### Step 5: Check the derivative at \( x = 2 \). Next, we will evaluate the derivative at \( x = 2 \). \[ f'(2) = 3(2^2 - 1) = 3(4 - 1) = 3 \cdot 3 = 9 \] ### Step 6: Analyze the result at \( x = 2 \). Since \( f'(2) = 9 \), which is greater than 0, we conclude that the function is monotonically increasing at \( x = 2 \). ### Final Conclusion: - At \( x = -1 \): The function is neither increasing nor decreasing (not monotonic). - At \( x = 2 \): The function is monotonically increasing. ---
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