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If `a_(1), a_(2), a_(3), a_(4), a_(5)` are consecutive terms of an arithmetic progression with common difference 3, then the value of `|(a_(3)^(2),a_(2),a_(1)),(a_(4)^(2),a_(3),a_(2)),(a_(5)^(2),a_(4),a_(3))|` is

A

0

B

27

C

81

D

162

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The correct Answer is:
To solve the problem, we need to evaluate the determinant given the terms of an arithmetic progression (AP). Let's break down the steps: ### Step 1: Define the terms of the AP Let the first term of the arithmetic progression be \( a_1 \). Since the common difference is 3, we can express the terms as follows: - \( a_1 = a_1 \) - \( a_2 = a_1 + 3 \) - \( a_3 = a_1 + 6 \) - \( a_4 = a_1 + 9 \) - \( a_5 = a_1 + 12 \) ### Step 2: Write the determinant We need to evaluate the determinant: \[ D = \begin{vmatrix} a_3^2 & a_2 & a_1 \\ a_4^2 & a_3 & a_2 \\ a_5^2 & a_4 & a_3 \end{vmatrix} \] ### Step 3: Substitute the terms into the determinant Substituting the expressions for \( a_1, a_2, a_3, a_4, a_5 \): - \( a_3^2 = (a_1 + 6)^2 = a_1^2 + 12a_1 + 36 \) - \( a_4^2 = (a_1 + 9)^2 = a_1^2 + 18a_1 + 81 \) - \( a_5^2 = (a_1 + 12)^2 = a_1^2 + 24a_1 + 144 \) Thus, the determinant becomes: \[ D = \begin{vmatrix} a_1^2 + 12a_1 + 36 & a_1 + 3 & a_1 \\ a_1^2 + 18a_1 + 81 & a_1 + 6 & a_1 + 3 \\ a_1^2 + 24a_1 + 144 & a_1 + 9 & a_1 + 6 \end{vmatrix} \] ### Step 4: Simplify the determinant using row operations We can use properties of determinants to simplify. We will perform the operation \( C_2 \leftarrow C_2 - C_3 \): \[ D = \begin{vmatrix} a_1^2 + 12a_1 + 36 & 3 & a_1 \\ a_1^2 + 18a_1 + 81 & 3 & a_1 + 3 \\ a_1^2 + 24a_1 + 144 & 3 & a_1 + 6 \end{vmatrix} \] ### Step 5: Factor out common terms Now, we can factor out the common term 3 from the second column: \[ D = 3 \begin{vmatrix} a_1^2 + 12a_1 + 36 & 1 & a_1 \\ a_1^2 + 18a_1 + 81 & 1 & a_1 + 3 \\ a_1^2 + 24a_1 + 144 & 1 & a_1 + 6 \end{vmatrix} \] ### Step 6: Use row operations again Next, we can perform \( R_2 \leftarrow R_2 - R_1 \) and \( R_3 \leftarrow R_3 - R_1 \): \[ D = 3 \begin{vmatrix} a_1^2 + 12a_1 + 36 & 1 & a_1 \\ 6a_1 + 45 & 0 & 3 \\ 12a_1 + 108 & 0 & 6 \end{vmatrix} \] ### Step 7: Calculate the determinant Now, we can calculate the determinant: \[ D = 3 \cdot 3 \cdot \begin{vmatrix} 1 & a_1 \\ 0 & 6 \end{vmatrix} = 3 \cdot 3 \cdot (1 \cdot 6 - 0 \cdot a_1) = 9 \cdot 6 = 54 \] ### Step 8: Substitute back the common difference Since the common difference \( D = 3 \), we can substitute back: \[ D = 54 \cdot D^2 = 54 \cdot 3^2 = 54 \cdot 9 = 486 \] ### Final Answer The value of the determinant is \( 486 \).
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