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If 1/(1^2)+1/(2^2)+1/(3^2)+ tooo=(pi^2)/...

If `1/(1^2)+1/(2^2)+1/(3^2)+ tooo=(pi^2)/6,t h e n1/(1^2)+1/(3^2)+1/(5^2)+` equals `pi^2//8` b. `pi^2//12` c. `pi^2//3` d. `pi^2//2`

A

`pi^2//8`

B

`pi^2//8`

C

`pi//3`

D

`pi^2//2`

Text Solution

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The correct Answer is:
To solve the problem, we need to find the value of the series: \[ S = \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \] We know from the problem statement that: \[ \frac{1}{1^2} + \frac{1}{2^2} + \frac{1}{3^2} + \frac{1}{4^2} + \frac{1}{5^2} + \ldots = \frac{\pi^2}{6} \] ### Step 1: Write the series for all integers The series for all integers can be expressed as: \[ \sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{\pi^2}{6} \] ### Step 2: Separate the series into odd and even terms We can separate this series into two parts: the series of odd integers and the series of even integers. \[ \sum_{n=1}^{\infty} \frac{1}{n^2} = \sum_{k=1}^{\infty} \frac{1}{(2k-1)^2} + \sum_{k=1}^{\infty} \frac{1}{(2k)^2} \] ### Step 3: Express the even terms The series for even integers can be expressed as: \[ \sum_{k=1}^{\infty} \frac{1}{(2k)^2} = \sum_{k=1}^{\infty} \frac{1}{4k^2} = \frac{1}{4} \sum_{k=1}^{\infty} \frac{1}{k^2} = \frac{1}{4} \cdot \frac{\pi^2}{6} = \frac{\pi^2}{24} \] ### Step 4: Substitute back into the equation Now we can substitute this back into our equation for the sum of all integers: \[ \frac{\pi^2}{6} = \sum_{k=1}^{\infty} \frac{1}{(2k-1)^2} + \frac{\pi^2}{24} \] ### Step 5: Solve for the sum of odd integers Let \( S = \sum_{k=1}^{\infty} \frac{1}{(2k-1)^2} \). Then we have: \[ \frac{\pi^2}{6} = S + \frac{\pi^2}{24} \] ### Step 6: Isolate \( S \) To isolate \( S \), we can subtract \( \frac{\pi^2}{24} \) from both sides: \[ S = \frac{\pi^2}{6} - \frac{\pi^2}{24} \] ### Step 7: Find a common denominator To perform the subtraction, we need a common denominator. The common denominator of 6 and 24 is 24. Thus, we rewrite \( \frac{\pi^2}{6} \): \[ \frac{\pi^2}{6} = \frac{4\pi^2}{24} \] Now substituting back: \[ S = \frac{4\pi^2}{24} - \frac{\pi^2}{24} = \frac{3\pi^2}{24} \] ### Step 8: Simplify Simplifying \( S \): \[ S = \frac{3\pi^2}{24} = \frac{\pi^2}{8} \] ### Conclusion Thus, the value of the series \( \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \) is: \[ \frac{\pi^2}{8} \] ### Final Answer The correct option is **(a)** \( \frac{\pi^2}{8} \). ---

To solve the problem, we need to find the value of the series: \[ S = \frac{1}{1^2} + \frac{1}{3^2} + \frac{1}{5^2} + \ldots \] We know from the problem statement that: ...
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