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In an A.P. if T(p) = q and T(p + q) = 0,...

In an A.P. if `T_(p) = q and T_(p + q) = 0`, then `T_(q)` is

A

p

B

`-p`

C

p + q

D

p - q

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find \( T_q \) in an arithmetic progression (A.P.) given that \( T_p = q \) and \( T_{p+q} = 0 \). ### Step-by-Step Solution: 1. **Understanding the Terms of A.P.**: The general term of an A.P. can be expressed as: \[ T_n = a + (n-1)d \] where \( a \) is the first term and \( d \) is the common difference. 2. **Setting Up the Equations**: From the problem, we have: - \( T_p = q \) - \( T_{p+q} = 0 \) Using the formula for the general term: \[ T_p = a + (p-1)d = q \quad \text{(1)} \] \[ T_{p+q} = a + (p+q-1)d = 0 \quad \text{(2)} \] 3. **Rearranging the Equations**: From equation (1): \[ a + (p-1)d = q \implies a = q - (p-1)d \quad \text{(3)} \] From equation (2): \[ a + (p+q-1)d = 0 \implies a = -(p+q-1)d \quad \text{(4)} \] 4. **Equating the Two Expressions for \( a \)**: Setting equation (3) equal to equation (4): \[ q - (p-1)d = -(p+q-1)d \] 5. **Simplifying the Equation**: Rearranging gives: \[ q - (p-1)d + (p+q-1)d = 0 \] \[ q + (p+q-1)d - (p-1)d = 0 \] \[ q + (p+q - p + 1)d = 0 \] \[ q + (q + 1)d = 0 \] \[ q + qd + d = 0 \] \[ q(1 + d) + d = 0 \] 6. **Solving for \( d \)**: Rearranging gives: \[ q(1 + d) = -d \] \[ q + qd + d = 0 \implies d(q + 1) = -q \] \[ d = \frac{-q}{q + 1} \quad \text{(5)} \] 7. **Finding \( T_q \)**: Now we need to find \( T_q \): \[ T_q = a + (q-1)d \] Substituting \( a \) from equation (4): \[ T_q = -(p+q-1)d + (q-1)d \] \[ = -pd - qd + d + qd - d \] \[ = -pd \] Substitute \( d \) from equation (5): \[ T_q = -p \left(\frac{-q}{q + 1}\right) = \frac{pq}{q + 1} \] ### Final Answer: Thus, \( T_q = p \).
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