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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 given for \( x \), \( y \), and \( z \) and find relationships between them. ### Step 1: Define the series We have: - \( x = \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \) (Sum of reciprocals of squares of odd numbers) - \( y = \frac{1}{1^2} + \frac{3}{2^2} + \frac{1}{3^2} + \frac{3}{4^2} + \ldots \) (Sum of reciprocals of squares of odd and even numbers with alternating coefficients) - \( z = \frac{1}{1^2} - \frac{1}{2^2} + \frac{1}{3^2} - \frac{1}{4^2} + \ldots \) (Alternating series of reciprocals of squares) ### Step 2: Analyze \( x - y \) To find \( x - y \): - The odd terms in \( y \) will cancel out with the corresponding terms in \( x \). - The remaining terms in \( y \) will be the even terms multiplied by 3: \[ x - y = -3 \left( \frac{1}{2^2} + \frac{1}{4^2} + \frac{1}{6^2} + \ldots \right) \] This series can be expressed as: \[ x - y = -3 \cdot \frac{1}{4} \left( \frac{1}{1^2} + \frac{1}{2^2} + \frac{1}{3^2} + \ldots \right) = -\frac{3}{4} \cdot \frac{\pi^2}{6} \] ### Step 3: Analyze \( x - z \) Now, for \( x - z \): - The odd terms in \( z \) will also cancel out with the corresponding terms in \( x \). - The remaining terms in \( z \) will be the even terms: \[ x - z = \left( \frac{1}{2^2} + \frac{1}{4^2} + \frac{1}{6^2} + \ldots \right) \] This series can be expressed as: \[ x - z = \frac{1}{4} \left( \frac{1}{1^2} + \frac{1}{2^2} + \frac{1}{3^2} + \ldots \right) = \frac{1}{4} \cdot \frac{\pi^2}{6} \] ### Step 4: Relate \( x - y \) and \( x - z \) From the results of \( x - y \) and \( x - z \): \[ x - y = -3(x - z) \] Substituting the expressions we derived: \[ -\frac{3}{4} \cdot \frac{\pi^2}{6} = -3 \cdot \frac{1}{4} \cdot \frac{\pi^2}{6} \] This shows a consistent relationship between the three series. ### Step 5: Final relationship From the derived relationships: \[ x - y = -3(x - z) \] We can express this as: \[ x - y + 3(x - z) = 0 \] This leads us to conclude: \[ 4x = y + 3z \] Dividing through by 6 gives: \[ \frac{2x}{3} = \frac{y}{6} + \frac{z}{2} \] ### Conclusion The relationship \( \frac{y}{6} = \frac{2x}{3} - \frac{z}{2} \) indicates that \( y/6 \), \( x/3 \), and \( z/2 \) are in arithmetic progression.

To solve the problem, we need to analyze the series given for \( x \), \( y \), and \( z \) and find relationships between them. ### Step 1: Define the series We have: - \( x = \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \) (Sum of reciprocals of squares of odd numbers) - \( y = \frac{1}{1^2} + \frac{3}{2^2} + \frac{1}{3^2} + \frac{3}{4^2} + \ldots \) (Sum of reciprocals of squares of odd and even numbers with alternating coefficients) - \( z = \frac{1}{1^2} - \frac{1}{2^2} + \frac{1}{3^2} - \frac{1}{4^2} + \ldots \) (Alternating series of reciprocals of squares) ...
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If x=(1)/(1^(2))+(1)/(3^(2))+(1)/(5^(2))+ . . . y=(1)/(1^(2))+(3)/(2^(2))+(1)/(3^(2))+(3)/(4^(2))+ . . . . z=(1)/(1^(2))-(1)/(2^(2))+(1)/(3^(2))-(1)/(4^(2))+ . . .then

((1)/(2)x^(2)-(1)/(2)y^(2)+(1)/(4)z^(2))-((1)/(3)x^2+(1)/(4)y^(2)+(1)/(2)z^(2))+((1)/(4)x^(2)+(1)/(3)y^(2)+(1)/(3)z^(2))

Simplify ((3(2)/(3))^(2)-(2 (1)/(2)))/((4(3)/(4))^(2)-(3(1)/(3))^(2))+(3(2)/(3)-2(1)/(2))/(4(3)/(4)-3(1)/(3))

(x+1)/(3)=(y+2)/(1)=(z+1)/(2) and (x-2)/(1)=(y+2)/(2)=(z-3)/(3)

(-(1)/(2)-(2)/(3)+(4)/(5)-(1)/(3)+(1)/(5)+(3)/(4))/((1)/(2)+(2)/(3)-(4)/(3)+(1)/(3)-(1)/(5)-(4)/(5)) is simplified to

5(1)/(2)-[2(1)/(3)-:[(3)/(4)-(1)/(2)times((2)/(3)-(1)/(24))]]

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