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Let f(x)=(e^(x))/(1+x^(2)) and g(x)=f'(x...

Let `f(x)=(e^(x))/(1+x^(2)) and g(x)=f'(x)` , then

A

g(x) has two local maxima and two local minima points

B

g(x) has exactly one local maxima and one local minima point

C

x = 1 is a point of local maxima for g(x)

D

There is a point of local maxima for g(x) in the interval (-1,0)

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To solve the problem, we need to analyze the function \( f(x) = \frac{e^x}{1 + x^2} \) and its derivative \( g(x) = f'(x) \) to find the maximum and minimum values. ### Step 1: Find the derivative of \( f(x) \) Using the quotient rule for differentiation, we have: \[ f'(x) = \frac{(1 + x^2)(e^x) - e^x(2x)}{(1 + x^2)^2} \] Simplifying this, we get: \[ f'(x) = \frac{e^x(1 + x^2 - 2x)}{(1 + x^2)^2} = \frac{e^x(1 - 2x + x^2)}{(1 + x^2)^2} \] ### Step 2: Set the derivative \( g(x) = f'(x) \) to zero To find critical points, we set the numerator equal to zero: \[ 1 - 2x + x^2 = 0 \] This is a quadratic equation. We can solve it using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{2 \pm \sqrt{(-2)^2 - 4 \cdot 1 \cdot 1}}{2 \cdot 1} = \frac{2 \pm \sqrt{4 - 4}}{2} = \frac{2 \pm 0}{2} = 1 \] ### Step 3: Analyze the critical point The only critical point we found is \( x = 1 \). To determine whether this point is a maximum or minimum, we can analyze the sign of \( f'(x) \) around this point. ### Step 4: Use the first derivative test We can check the sign of \( f'(x) \) for values less than and greater than 1: - For \( x < 1 \), say \( x = 0 \): \[ f'(0) = \frac{e^0(1 - 0)}{(1 + 0)^2} = 1 > 0 \quad (\text{increasing}) \] - For \( x > 1 \), say \( x = 2 \): \[ f'(2) = \frac{e^2(1 - 4 + 4)}{(1 + 4)^2} = \frac{e^2(1)}{25} > 0 \quad (\text{increasing}) \] Since \( f'(x) \) changes from positive to negative at \( x = 1 \), we conclude that \( x = 1 \) is a local maximum. ### Step 5: Determine the behavior as \( x \to \pm \infty \) As \( x \to \infty \): \[ f(x) \to 0 \quad \text{(since \( e^x \) grows faster than \( 1 + x^2 \))} \] As \( x \to -\infty \): \[ f(x) \to 0 \quad \text{(since \( e^x \to 0 \))} \] ### Conclusion The function \( f(x) \) has a local maximum at \( x = 1 \) and approaches 0 as \( x \to \pm \infty \). Therefore, the maximum value occurs at \( x = 1 \).

To solve the problem, we need to analyze the function \( f(x) = \frac{e^x}{1 + x^2} \) and its derivative \( g(x) = f'(x) \) to find the maximum and minimum values. ### Step 1: Find the derivative of \( f(x) \) Using the quotient rule for differentiation, we have: \[ f'(x) = \frac{(1 + x^2)(e^x) - e^x(2x)}{(1 + x^2)^2} ...
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