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The sum of first 50 term of the series ...

The sum of first 50 term of the series `1+3/2+7/4+15/8+31/16+`….. Is `(p+1/(2^(q)))`, then value of `(p+q)` is …….

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To find the sum of the first 50 terms of the series \(1 + \frac{3}{2} + \frac{7}{4} + \frac{15}{8} + \frac{31}{16} + \ldots\), we can start by identifying a pattern in the series. ### Step 1: Identify the general term of the series The numerators of the series appear to follow a pattern: - The first term is \(1 = 2^1 - 1\) - The second term is \(3 = 2^2 - 1\) - The third term is \(7 = 2^3 - 1\) - The fourth term is \(15 = 2^4 - 1\) - The fifth term is \(31 = 2^5 - 1\) Thus, the \(n\)-th term can be expressed as: \[ a_n = \frac{2^n - 1}{2^{n-1}} \] ### Step 2: Rewrite the series We can rewrite the series using the general term: \[ S_n = \sum_{n=1}^{50} a_n = \sum_{n=1}^{50} \left( \frac{2^n - 1}{2^{n-1}} \right) = \sum_{n=1}^{50} \left( 2 - \frac{1}{2^{n-1}} \right) \] ### Step 3: Split the sum Now, we can separate the sum into two parts: \[ S_n = \sum_{n=1}^{50} 2 - \sum_{n=1}^{50} \frac{1}{2^{n-1}} \] The first sum is straightforward: \[ \sum_{n=1}^{50} 2 = 2 \times 50 = 100 \] ### Step 4: Calculate the second sum The second sum is a geometric series: \[ \sum_{n=1}^{50} \frac{1}{2^{n-1}} = 1 + \frac{1}{2} + \frac{1}{4} + \ldots + \frac{1}{2^{49}} \] This is a geometric series with first term \(a = 1\) and common ratio \(r = \frac{1}{2}\). The sum of the first \(n\) terms of a geometric series is given by: \[ S_n = \frac{a(1 - r^n)}{1 - r} \] Substituting in our values: \[ S_{50} = \frac{1(1 - (1/2)^{50})}{1 - 1/2} = \frac{1 - \frac{1}{2^{50}}}{\frac{1}{2}} = 2(1 - \frac{1}{2^{50}}) = 2 - \frac{2}{2^{50}} = 2 - \frac{1}{2^{49}} \] ### Step 5: Combine the results Now substituting back into our expression for \(S_n\): \[ S_n = 100 - \left(2 - \frac{1}{2^{49}}\right) = 100 - 2 + \frac{1}{2^{49}} = 98 + \frac{1}{2^{49}} \] ### Step 6: Identify \(p\) and \(q\) From the final expression, we can see that: \[ S_n = 98 + \frac{1}{2^{49}} \] Thus, \(p = 98\) and \(q = 49\). ### Step 7: Calculate \(p + q\) Now, we find: \[ p + q = 98 + 49 = 147 \] ### Final Answer The value of \(p + q\) is \(147\).

To find the sum of the first 50 terms of the series \(1 + \frac{3}{2} + \frac{7}{4} + \frac{15}{8} + \frac{31}{16} + \ldots\), we can start by identifying a pattern in the series. ### Step 1: Identify the general term of the series The numerators of the series appear to follow a pattern: - The first term is \(1 = 2^1 - 1\) - The second term is \(3 = 2^2 - 1\) - The third term is \(7 = 2^3 - 1\) - The fourth term is \(15 = 2^4 - 1\) ...
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