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Let Delta(1)=|{:(ap^(2),2ap,1),(aq^(2),2...

Let `Delta_(1)=|{:(ap^(2),2ap,1),(aq^(2),2aq,1),(ar^(2),2ar,1):}|` and `Delta_(2)=|{:(apq,a(p+q),1),(aqr,a(q+r),1),(arp,a(r+p),1):}|` then

A

`Delta_(1)=Delta_(2)`

B

`Delta_(2)=2Delta_(1)`

C

`Delta_(1)=2Delta_(2)`

D

`Delta_(1)+2Delta_(2)=0`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given problem, we need to evaluate the determinants \( \Delta_1 \) and \( \Delta_2 \) and then compare them based on the options provided. ### Step-by-Step Solution: 1. **Evaluate \( \Delta_1 \)**: \[ \Delta_1 = \begin{vmatrix} ap^2 & 2ap & 1 \\ aq^2 & 2aq & 1 \\ ar^2 & 2ar & 1 \end{vmatrix} \] We can factor out \( a \) from the first column and \( 2 \) from the second column: \[ \Delta_1 = 2a \begin{vmatrix} p^2 & 1 \\ q^2 & 1 \\ r^2 & 1 \end{vmatrix} \] 2. **Row Operations**: Now we apply row operations to simplify the determinant: \[ R_1 \rightarrow R_1 - R_2 \quad \text{and} \quad R_2 \rightarrow R_2 - R_3 \] This gives: \[ \Delta_1 = 2a \begin{vmatrix} p^2 - q^2 & 0 \\ q^2 - r^2 & 0 \\ r^2 & 1 \end{vmatrix} \] 3. **Factor the Determinant**: The determinant can now be factored as: \[ \Delta_1 = 2a \cdot (p - q)(p + q) \cdot (q - r)(q + r) \cdot (r - p)(r + p) \] 4. **Evaluate \( \Delta_2 \)**: \[ \Delta_2 = \begin{vmatrix} apq & a(p + q) & 1 \\ aqr & a(q + r) & 1 \\ arp & a(r + p) & 1 \end{vmatrix} \] Again, we can factor out \( a \) from the first column: \[ \Delta_2 = a^2 \begin{vmatrix} pq & p + q & 1 \\ qr & q + r & 1 \\ rp & r + p & 1 \end{vmatrix} \] 5. **Row Operations**: Applying the same row operations: \[ R_1 \rightarrow R_1 - R_2 \quad \text{and} \quad R_2 \rightarrow R_2 - R_3 \] This gives: \[ \Delta_2 = a^2 \begin{vmatrix} pq - qr & p + q - (q + r) & 0 \\ qr - rp & q + r - (r + p) & 0 \\ rp & r + p & 1 \end{vmatrix} \] 6. **Factor the Determinant**: The determinant simplifies to: \[ \Delta_2 = a^2 \cdot (p - r)(q - p)(q - r) \] 7. **Compare \( \Delta_1 \) and \( \Delta_2 \)**: From the calculations, we have: \[ \Delta_1 = 2a^2 (p - q)(q - r)(r - p) \] \[ \Delta_2 = a^2 (p - r)(q - p)(q - r) \] Therefore, we can conclude: \[ \Delta_1 = 2 \Delta_2 \] ### Final Conclusion: The correct option is that \( \Delta_1 = 2 \Delta_2 \).

To solve the given problem, we need to evaluate the determinants \( \Delta_1 \) and \( \Delta_2 \) and then compare them based on the options provided. ### Step-by-Step Solution: 1. **Evaluate \( \Delta_1 \)**: \[ \Delta_1 = \begin{vmatrix} ap^2 & 2ap & 1 \\ ...
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