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If x=(1)/(1^(2))+(1)/(3^(2))+(1)/(5^(2))...

If `x=(1)/(1^(2))+(1)/(3^(2))+(1)/(5^(2))+....` , `y=(1)/(1^(2))+(3)/(2^(2))+(1)/(3^(2))+(3)/(4^(2))+....` and `z=(1)/(1^(2))-(1)/(2^(2))+(1)/(3^(2))-(1)/(4^(2))+...` then

A

`x`, `y`,`z` are in `A.P.`

B

`(y)/(6)`, `(x)/(3)`,`(z)/(2)` are in `A.P.`

C

`(y)/(6)`, `(x)/(3)`,`(z)/(2)` are in `A.P.`

D

`6y`, `3x`, `2z` are in `H.P.`

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To solve the problem, we need to analyze the series for \( x \), \( y \), and \( z \) and determine their relationships. ### Step 1: Define the series 1. **Define \( x \)**: \[ x = \sum_{n=0}^{\infty} \frac{1}{(2n+1)^2} = \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \] 2. **Define \( y \)**: \[ y = \sum_{n=1}^{\infty} \frac{1}{n^2} + \sum_{n=1}^{\infty} \frac{3}{(n+1)^2} = \frac{1}{1^2} + \frac{3}{2^2} + \frac{1}{3^2} + \frac{3}{4^2} + \ldots \] 3. **Define \( z \)**: \[ z = \sum_{n=1}^{\infty} \frac{(-1)^{n-1}}{n^2} = \frac{1}{1^2} - \frac{1}{2^2} + \frac{1}{3^2} - \frac{1}{4^2} + \ldots \] ### Step 2: Analyze \( y - x \) To find the relationship between \( y \) and \( x \): \[ y - x = \left( \frac{1}{1^2} + \frac{3}{2^2} + \frac{1}{3^2} + \frac{3}{4^2} + \ldots \right) - \left( \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \right) \] Notice that the terms with odd denominators in \( x \) will cancel out with those in \( y \). The remaining terms will be: \[ y - x = \sum_{n=1}^{\infty} \frac{3}{(2n)^2} = 3 \sum_{n=1}^{\infty} \frac{1}{(2n)^2} = 3 \cdot \frac{1}{4} \sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{3}{4} \cdot \frac{\pi^2}{6} \] ### Step 3: Analyze \( x - z \) Now, consider \( x - z \): \[ x - z = \left( \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \right) - \left( \frac{1}{1^2} - \frac{1}{2^2} + \frac{1}{3^2} - \frac{1}{4^2} + \ldots \right) \] Here, the terms with \( \frac{1}{1^2} \) and \( \frac{1}{3^2} \) will cancel out, and we are left with: \[ x - z = \sum_{n=1}^{\infty} \frac{1}{(2n)^2} = \frac{1}{4} \sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{\pi^2}{24} \] ### Step 4: Establish the relationship From the previous steps, we have: 1. \( y - x = \frac{3}{4} \cdot \frac{\pi^2}{6} \) 2. \( x - z = \frac{\pi^2}{24} \) Now, we can express these relationships: \[ y - x = 3(x - z) \] This implies: \[ y + 3z = 4x \] ### Step 5: Conclusion From the equation \( y + 3z = 4x \), we can rearrange it to show that: \[ \frac{y}{6} + \frac{3z}{6} = \frac{4x}{6} \] This indicates that \( \frac{y}{6}, \frac{3z}{6}, \frac{4x}{6} \) are in Arithmetic Progression (AP). Thus, the correct answer is that \( \frac{y}{6}, \frac{3z}{6}, \frac{4x}{6} \) are in AP.

To solve the problem, we need to analyze the series for \( x \), \( y \), and \( z \) and determine their relationships. ### Step 1: Define the series 1. **Define \( x \)**: \[ x = \sum_{n=0}^{\infty} \frac{1}{(2n+1)^2} = \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \] ...
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