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If the first two terms of a H.P. are 2//...

If the first two terms of a H.P. are `2//5and12//23` respectively. Then, largest term is

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To solve the problem step by step, we will follow the process of finding the terms of the Harmonic Progression (H.P.) and determining the largest term. ### Step 1: Understanding the terms of H.P. The first two terms of the H.P. are given as \( \frac{2}{5} \) and \( \frac{12}{23} \). In a Harmonic Progression, the reciprocals of the terms form an Arithmetic Progression (A.P.). ### Step 2: Finding the first two terms of A.P. Let the first term of the corresponding A.P. be \( a \) and the common difference be \( d \). Therefore, we have: - First term: \( \frac{1}{\frac{2}{5}} = \frac{5}{2} \) - Second term: \( \frac{1}{\frac{12}{23}} = \frac{23}{12} \) ### Step 3: Setting up the equations From the above, we can set up the following equations: 1. \( a = \frac{5}{2} \) 2. \( a + d = \frac{23}{12} \) ### Step 4: Solving for \( d \) Substituting \( a \) into the second equation: \[ \frac{5}{2} + d = \frac{23}{12} \] To solve for \( d \), we first convert \( \frac{5}{2} \) to have a common denominator of 12: \[ \frac{5}{2} = \frac{30}{12} \] Now substituting: \[ \frac{30}{12} + d = \frac{23}{12} \] Subtracting \( \frac{30}{12} \) from both sides gives: \[ d = \frac{23}{12} - \frac{30}{12} = -\frac{7}{12} \] ### Step 5: Finding the nth term of H.P. The nth term of the H.P. can be expressed as: \[ H_n = \frac{1}{a + (n-1)d} \] Substituting the values of \( a \) and \( d \): \[ H_n = \frac{1}{\frac{5}{2} + (n-1)(-\frac{7}{12})} \] This simplifies to: \[ H_n = \frac{1}{\frac{5}{2} - \frac{7(n-1)}{12}} \] ### Step 6: Finding a common denominator To simplify further, convert \( \frac{5}{2} \) to a fraction with a denominator of 12: \[ \frac{5}{2} = \frac{30}{12} \] Thus, \[ H_n = \frac{1}{\frac{30 - 7(n-1)}{12}} = \frac{12}{30 - 7(n-1)} \] This can be rewritten as: \[ H_n = \frac{12}{37 - 7n} \] ### Step 7: Finding the largest term To find the largest term, we need to minimize the denominator \( 37 - 7n \) while ensuring it remains positive: \[ 37 - 7n > 0 \implies n < \frac{37}{7} \approx 5.2857 \] Thus, the maximum integer \( n \) can take is 5. ### Step 8: Calculating the 5th term Substituting \( n = 5 \): \[ H_5 = \frac{12}{37 - 7 \times 5} = \frac{12}{37 - 35} = \frac{12}{2} = 6 \] ### Conclusion The largest term in the given H.P. is \( 6 \). ---

To solve the problem step by step, we will follow the process of finding the terms of the Harmonic Progression (H.P.) and determining the largest term. ### Step 1: Understanding the terms of H.P. The first two terms of the H.P. are given as \( \frac{2}{5} \) and \( \frac{12}{23} \). In a Harmonic Progression, the reciprocals of the terms form an Arithmetic Progression (A.P.). ### Step 2: Finding the first two terms of A.P. Let the first term of the corresponding A.P. be \( a \) and the common difference be \( d \). Therefore, we have: - First term: \( \frac{1}{\frac{2}{5}} = \frac{5}{2} \) ...
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