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If Delta=|{:(1,a,a^(2)),(a,a^(2),1),(a^(...

If `Delta=|{:(1,a,a^(2)),(a,a^(2),1),(a^(2),1,a):}|=-4`, then find the value of :
`|{:(a^(3)-1,0,a-a^(4)),(0,a-a^(4),a^(3)-1),(a-a^(4),a^(3)-1,0):}|`

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To solve the problem, we start with the given determinant: \[ \Delta = \begin{vmatrix} 1 & a & a^2 \\ a & a^2 & 1 \\ a^2 & 1 & a \end{vmatrix} = -4 \] We need to find the value of the determinant: \[ D = \begin{vmatrix} a^3 - 1 & 0 & a - a^4 \\ 0 & a - a^4 & a^3 - 1 \\ a - a^4 & a^3 - 1 & 0 \end{vmatrix} \] ### Step 1: Factor out common terms Notice that \(a - a^4 = a(1 - a^3)\). We can factor \(a(1 - a^3)\) out of the second and third rows. \[ D = a(1 - a^3) \begin{vmatrix} a^3 - 1 & 0 & 1 \\ 0 & 1 & a^3 - 1 \\ 1 & a^3 - 1 & 0 \end{vmatrix} \] ### Step 2: Evaluate the new determinant Now we will evaluate the determinant: \[ D = a(1 - a^3) \begin{vmatrix} a^3 - 1 & 0 & 1 \\ 0 & 1 & a^3 - 1 \\ 1 & a^3 - 1 & 0 \end{vmatrix} \] We can expand this determinant along the first row: \[ = (a^3 - 1) \begin{vmatrix} 1 & a^3 - 1 \\ a^3 - 1 & 0 \end{vmatrix} - 0 + 1 \begin{vmatrix} 0 & 1 \\ 1 & a^3 - 1 \end{vmatrix} \] Calculating the first determinant: \[ \begin{vmatrix} 1 & a^3 - 1 \\ a^3 - 1 & 0 \end{vmatrix} = 1 \cdot 0 - (a^3 - 1)(a^3 - 1) = -(a^3 - 1)^2 \] Calculating the second determinant: \[ \begin{vmatrix} 0 & 1 \\ 1 & a^3 - 1 \end{vmatrix} = 0 \cdot (a^3 - 1) - 1 \cdot 1 = -1 \] Putting it all together: \[ D = (a^3 - 1)(-(a^3 - 1)^2) + 1(-1) = -(a^3 - 1)^3 - 1 \] ### Step 3: Substitute \(a^3 - 1\) From the original determinant, we know that \(a^3 - 1 = \pm 4\). We need to evaluate \(D\) for both cases. 1. If \(a^3 - 1 = 4\): \[ D = -4^3 - 1 = -64 - 1 = -65 \] 2. If \(a^3 - 1 = -4\): \[ D = -(-4)^3 - 1 = 64 - 1 = 63 \] ### Final Answer Thus, the value of the determinant \(D\) can be either \(-65\) or \(63\) depending on the value of \(a^3 - 1\).
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