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If a1,a2,….an are in H.P then (a1)/(a...

If `a_1,a_2,….a_n` are in H.P then `(a_1)/(a_2+,a_3,…,a_n),(a_2)/(a_1+a_3+….+a_n),…,(a_n)/(a_1+a_2+….+a_(n-1))`
are in

A

A.P

B

G.P

C

H.P

D

none of these

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To determine if the sequence \(\left( \frac{a_1}{a_2 + a_3 + \ldots + a_n}, \frac{a_2}{a_1 + a_3 + \ldots + a_n}, \ldots, \frac{a_n}{a_1 + a_2 + \ldots + a_{n-1}} \right)\) is in Harmonic Progression (H.P), we start by recalling that if \(a_1, a_2, \ldots, a_n\) are in H.P, then their reciprocals \( \frac{1}{a_1}, \frac{1}{a_2}, \ldots, \frac{1}{a_n} \) are in Arithmetic Progression (A.P). ### Step-by-step Solution: 1. **Understanding H.P and A.P**: Since \(a_1, a_2, \ldots, a_n\) are in H.P, we know that: \[ \frac{1}{a_1}, \frac{1}{a_2}, \ldots, \frac{1}{a_n} \text{ are in A.P.} \] 2. **Expressing the Terms**: The terms we need to analyze are: \[ b_1 = \frac{a_1}{a_2 + a_3 + \ldots + a_n}, \quad b_2 = \frac{a_2}{a_1 + a_3 + \ldots + a_n}, \quad \ldots, \quad b_n = \frac{a_n}{a_1 + a_2 + \ldots + a_{n-1}}. \] 3. **Finding a Common Denominator**: We can express the denominators in a more manageable form. Let: \[ S = a_1 + a_2 + \ldots + a_n. \] Then the terms can be rewritten as: \[ b_1 = \frac{a_1}{S - a_1}, \quad b_2 = \frac{a_2}{S - a_2}, \quad \ldots, \quad b_n = \frac{a_n}{S - a_n}. \] 4. **Identifying the A.P**: Since \( \frac{1}{a_1}, \frac{1}{a_2}, \ldots, \frac{1}{a_n} \) are in A.P, we can express the condition for A.P: \[ 2 \cdot \frac{1}{a_k} = \frac{1}{a_{k-1}} + \frac{1}{a_{k+1}} \quad \text{for } k = 2, 3, \ldots, n-1. \] 5. **Reciprocal of the Terms**: The terms \(b_k\) can be expressed in terms of their reciprocals: \[ \frac{1}{b_k} = \frac{S - a_k}{a_k}. \] Thus, we can see that if \(b_k\) are in H.P, then \(\frac{1}{b_k}\) must be in A.P. 6. **Conclusion**: Since we have shown that the sequence \(\left( \frac{1}{b_1}, \frac{1}{b_2}, \ldots, \frac{1}{b_n} \right)\) is in A.P, it follows that the sequence \(b_1, b_2, \ldots, b_n\) is in H.P. ### Final Answer: Thus, the sequence \(\left( \frac{a_1}{a_2 + a_3 + \ldots + a_n}, \frac{a_2}{a_1 + a_3 + \ldots + a_n}, \ldots, \frac{a_n}{a_1 + a_2 + \ldots + a_{n-1}} \right)\) is in **Harmonic Progression (H.P)**.

To determine if the sequence \(\left( \frac{a_1}{a_2 + a_3 + \ldots + a_n}, \frac{a_2}{a_1 + a_3 + \ldots + a_n}, \ldots, \frac{a_n}{a_1 + a_2 + \ldots + a_{n-1}} \right)\) is in Harmonic Progression (H.P), we start by recalling that if \(a_1, a_2, \ldots, a_n\) are in H.P, then their reciprocals \( \frac{1}{a_1}, \frac{1}{a_2}, \ldots, \frac{1}{a_n} \) are in Arithmetic Progression (A.P). ### Step-by-step Solution: 1. **Understanding H.P and A.P**: Since \(a_1, a_2, \ldots, a_n\) are in H.P, we know that: \[ \frac{1}{a_1}, \frac{1}{a_2}, \ldots, \frac{1}{a_n} \text{ are in A.P.} ...
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