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Is the function f(x)=x^(2), x in R incre...

Is the function `f(x)=x^(2), x in R` increasing?

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To determine if the function \( f(x) = x^2 \) is increasing for all \( x \in \mathbb{R} \), we will follow these steps: ### Step 1: Find the derivative of the function To analyze whether the function is increasing, we first need to find its derivative. The derivative of \( f(x) = x^2 \) is calculated as follows: \[ f'(x) = \frac{d}{dx}(x^2) = 2x \] ### Step 2: Analyze the sign of the derivative Next, we need to determine when the derivative \( f'(x) = 2x \) is greater than or equal to zero. This will help us identify the intervals where the function is increasing. \[ f'(x) \geq 0 \implies 2x \geq 0 \] Dividing both sides by 2 (which does not change the inequality since 2 is positive): \[ x \geq 0 \] ### Step 3: Determine the intervals of increase From the inequality \( x \geq 0 \), we can conclude that the function \( f(x) = x^2 \) is increasing for all \( x \) in the interval \( [0, \infty) \). ### Step 4: Check the behavior for negative values Now, we check the behavior of the function for \( x < 0 \): \[ f'(x) < 0 \text{ for } x < 0 \] This indicates that the function is decreasing for all negative values of \( x \). ### Conclusion Thus, the function \( f(x) = x^2 \) is not increasing for all \( x \in \mathbb{R} \). It is increasing only on the interval \( [0, \infty) \) and decreasing on \( (-\infty, 0) \). ### Final Answer The function \( f(x) = x^2 \) is not increasing for all real numbers \( x \). ---
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