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For the series S=1+(1)/((1+3))(1+2)^(2)+...

For the series `S=1+(1)/((1+3))(1+2)^(2)+(1)/((1+3+5))(1+2+3)^(2)+(1)/((1+3+5+7))(1+2+3+4)^(2)+………..,` if the sum of the first 10 terms is K, then `(4K)/(101)` is equal to

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To solve the given series \( S = 1 + \frac{1}{(1+3)(1+2)^2} + \frac{1}{(1+3+5)(1+2+3)^2} + \frac{1}{(1+3+5+7)(1+2+3+4)^2} + \ldots \), we will follow these steps: ### Step 1: Identify the pattern in the series The series can be expressed in terms of sums of odd numbers and squares of sums of natural numbers. The \( n \)-th term can be represented as: \[ T_n = \frac{1}{(1 + 3 + 5 + \ldots + (2n-1))(1 + 2 + 3 + \ldots + n)^2} \] ### Step 2: Calculate the sums in the denominator The sum of the first \( n \) odd numbers is given by: \[ 1 + 3 + 5 + \ldots + (2n-1) = n^2 \] The sum of the first \( n \) natural numbers is given by: \[ 1 + 2 + 3 + \ldots + n = \frac{n(n+1)}{2} \] Thus, the square of this sum is: \[ \left( \frac{n(n+1)}{2} \right)^2 = \frac{n^2(n+1)^2}{4} \] ### Step 3: Substitute back into the term Now substituting these results back into \( T_n \): \[ T_n = \frac{1}{n^2 \cdot \frac{n^2(n+1)^2}{4}} = \frac{4}{n^4(n+1)^2} \] ### Step 4: Write the series in terms of \( T_n \) The series \( S \) can now be expressed as: \[ S = \sum_{n=1}^{\infty} T_n = \sum_{n=1}^{\infty} \frac{4}{n^4(n+1)^2} \] ### Step 5: Calculate the first 10 terms To find \( K \), the sum of the first 10 terms, we compute: \[ K = \sum_{n=1}^{10} T_n = \sum_{n=1}^{10} \frac{4}{n^4(n+1)^2} \] Calculating each term: - For \( n = 1 \): \( T_1 = \frac{4}{1^4 \cdot 2^2} = 1 \) - For \( n = 2 \): \( T_2 = \frac{4}{2^4 \cdot 3^2} = \frac{4}{16 \cdot 9} = \frac{1}{36} \) - For \( n = 3 \): \( T_3 = \frac{4}{3^4 \cdot 4^2} = \frac{4}{81 \cdot 16} = \frac{1}{324} \) - For \( n = 4 \): \( T_4 = \frac{4}{4^4 \cdot 5^2} = \frac{4}{256 \cdot 25} = \frac{1}{1600} \) - For \( n = 5 \): \( T_5 = \frac{4}{5^4 \cdot 6^2} = \frac{4}{625 \cdot 36} = \frac{1}{5625} \) - For \( n = 6 \): \( T_6 = \frac{4}{6^4 \cdot 7^2} = \frac{4}{1296 \cdot 49} = \frac{1}{63504} \) - For \( n = 7 \): \( T_7 = \frac{4}{7^4 \cdot 8^2} = \frac{4}{2401 \cdot 64} = \frac{1}{153664} \) - For \( n = 8 \): \( T_8 = \frac{4}{8^4 \cdot 9^2} = \frac{4}{4096 \cdot 81} = \frac{1}{331776} \) - For \( n = 9 \): \( T_9 = \frac{4}{9^4 \cdot 10^2} = \frac{4}{6561 \cdot 100} = \frac{1}{2624400} \) - For \( n = 10 \): \( T_{10} = \frac{4}{10^4 \cdot 11^2} = \frac{4}{10000 \cdot 121} = \frac{1}{3025000} \) ### Step 6: Sum the first 10 terms Calculating \( K \): \[ K = 1 + \frac{1}{36} + \frac{1}{324} + \frac{1}{1600} + \frac{1}{5625} + \frac{1}{63504} + \frac{1}{153664} + \frac{1}{331776} + \frac{1}{2624400} + \frac{1}{3025000} \] This sum can be approximated numerically. ### Step 7: Calculate \( \frac{4K}{101} \) Finally, we compute: \[ \frac{4K}{101} \] Using the approximate value of \( K \) calculated from the sum of the first 10 terms.

To solve the given series \( S = 1 + \frac{1}{(1+3)(1+2)^2} + \frac{1}{(1+3+5)(1+2+3)^2} + \frac{1}{(1+3+5+7)(1+2+3+4)^2} + \ldots \), we will follow these steps: ### Step 1: Identify the pattern in the series The series can be expressed in terms of sums of odd numbers and squares of sums of natural numbers. The \( n \)-th term can be represented as: \[ T_n = \frac{1}{(1 + 3 + 5 + \ldots + (2n-1))(1 + 2 + 3 + \ldots + n)^2} \] ...
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