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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 analyze the series and derive a formula for the \(n^{th}\) term. ### Step 1: Identify the pattern in the series The series can be expressed as: \[ \frac{1}{2^0} + \frac{3}{2^1} + \frac{7}{2^2} + \frac{15}{2^3} + \frac{31}{2^4} + \ldots \] We can observe that the numerators follow a pattern: - \(1 = 2^1 - 1\) - \(3 = 2^2 - 1\) - \(7 = 2^3 - 1\) - \(15 = 2^4 - 1\) - \(31 = 2^5 - 1\) Thus, the \(n^{th}\) term can be expressed as: \[ a_n = \frac{2^{n+1} - 1}{2^n} \] ### Step 2: Rewrite the \(n^{th}\) term We can rewrite \(a_n\) as: \[ a_n = 2 - \frac{1}{2^n} \] ### Step 3: Sum the first 50 terms Now, we need to find the sum of the first 50 terms: \[ S_{50} = \sum_{n=0}^{49} a_n = \sum_{n=0}^{49} \left(2 - \frac{1}{2^n}\right) \] This can be split into two separate sums: \[ S_{50} = \sum_{n=0}^{49} 2 - \sum_{n=0}^{49} \frac{1}{2^n} \] ### Step 4: Calculate the first sum The first sum is: \[ \sum_{n=0}^{49} 2 = 2 \times 50 = 100 \] ### Step 5: Calculate the second sum The second sum is a geometric series: \[ \sum_{n=0}^{49} \frac{1}{2^n} = \frac{1 - \left(\frac{1}{2}\right)^{50}}{1 - \frac{1}{2}} = 2 \left(1 - \frac{1}{2^{50}}\right) \] ### Step 6: Combine the results Now, substituting back into the sum: \[ S_{50} = 100 - 2 \left(1 - \frac{1}{2^{50}}\right) = 100 - 2 + \frac{2}{2^{50}} = 98 + \frac{1}{2^{49}} \] ### Step 7: Express in the required form We have: \[ S_{50} = 98 + \frac{1}{2^{49}} \] This matches the form \(p + \frac{1}{2^q}\) where \(p = 98\) and \(q = 49\). ### Step 8: Calculate \(p + q\) Now, we find: \[ p + q = 98 + 49 = 147 \] Thus, the final answer is: \[ \boxed{147} \]

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 analyze the series and derive a formula for the \(n^{th}\) term. ### Step 1: Identify the pattern in the series The series can be expressed as: \[ \frac{1}{2^0} + \frac{3}{2^1} + \frac{7}{2^2} + \frac{15}{2^3} + \frac{31}{2^4} + \ldots \] ...
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