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Let f(theta)=1/(1+(cottheta)^x)and S=sum...

Let `f(theta)=1/(1+(cottheta)^x)and S=sum_(theta=1^@)^(89^@) f(theta)`, then the value of `S` is _________ .

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To solve the problem, we need to evaluate the function \( f(\theta) = \frac{1}{1 + (\cot \theta)^x} \) and then find the sum \( S = \sum_{\theta=1}^{89} f(\theta) \). ### Step-by-Step Solution: 1. **Understanding the Function**: The function is given as: \[ f(\theta) = \frac{1}{1 + (\cot \theta)^x} \] We can rewrite \( \cot \theta \) in terms of \( \tan \theta \): \[ \cot \theta = \frac{1}{\tan \theta} \] Thus, we have: \[ f(\theta) = \frac{1}{1 + \left(\frac{1}{\tan \theta}\right)^x} = \frac{1}{1 + \frac{1}{(\tan \theta)^x}} = \frac{\tan^x \theta}{\tan^x \theta + 1} \] 2. **Finding \( f(90 - \theta) \)**: Next, we evaluate \( f(90 - \theta) \): \[ f(90 - \theta) = \frac{1}{1 + \cot(90 - \theta)^x} = \frac{1}{1 + \tan \theta^x} = \frac{1}{1 + (\tan \theta)^x} \] This can also be rewritten as: \[ f(90 - \theta) = \frac{1}{1 + \tan^x \theta} \] 3. **Adding \( f(\theta) \) and \( f(90 - \theta) \)**: Now, we add \( f(\theta) \) and \( f(90 - \theta) \): \[ f(\theta) + f(90 - \theta) = \frac{\tan^x \theta}{\tan^x \theta + 1} + \frac{1}{1 + \tan^x \theta} \] Simplifying this: \[ = \frac{\tan^x \theta + 1}{\tan^x \theta + 1} = 1 \] This shows that \( f(\theta) + f(90 - \theta) = 1 \). 4. **Summing \( S \)**: The sum \( S \) can be expressed as: \[ S = \sum_{\theta=1}^{89} f(\theta) \] We can pair the terms: \[ S = (f(1) + f(89)) + (f(2) + f(88)) + \ldots + (f(44) + f(46)) + f(45) \] Each pair \( f(\theta) + f(90 - \theta) = 1 \) contributes 1 to the sum. There are 44 such pairs from \( \theta = 1 \) to \( 44 \). 5. **Calculating \( f(45) \)**: Now we need to calculate \( f(45) \): \[ f(45) = \frac{1}{1 + \cot(45)^x} = \frac{1}{1 + 1^x} = \frac{1}{1 + 1} = \frac{1}{2} \] 6. **Final Calculation**: Thus, the total sum \( S \) is: \[ S = 44 \cdot 1 + \frac{1}{2} = 44 + 0.5 = 44.5 \] ### Final Answer: The value of \( S \) is \( \boxed{44.5} \).

To solve the problem, we need to evaluate the function \( f(\theta) = \frac{1}{1 + (\cot \theta)^x} \) and then find the sum \( S = \sum_{\theta=1}^{89} f(\theta) \). ### Step-by-Step Solution: 1. **Understanding the Function**: The function is given as: \[ f(\theta) = \frac{1}{1 + (\cot \theta)^x} ...
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