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If w ne 1 is a cube root of unity and De...

If `w ne 1` is a cube root of unity and `Delta=|{:(x+w^(2),w,1),(w,w^(2),1+x),(1,x+w,w^(2)):}|=0`, then value of `x` is

A

`0`

B

`2`

C

`-1`

D

None of these

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The correct Answer is:
To solve the given determinant problem, we start with the determinant defined as: \[ \Delta = \begin{vmatrix} x + \omega^2 & \omega & 1 \\ \omega & \omega^2 & 1 + x \\ 1 & x + \omega & \omega^2 \end{vmatrix} \] where \( \omega \) is a cube root of unity and \( \omega \neq 1 \). ### Step 1: Apply Column Transformation We can simplify the determinant by applying the column transformation \( C_1 = C_1 + C_2 + C_3 \). This gives us: \[ \Delta = \begin{vmatrix} (x + \omega^2) + \omega + 1 & \omega & 1 \\ \omega + \omega^2 + (1 + x) & \omega^2 & 1 + x \\ 1 + (x + \omega) + \omega^2 & x + \omega & \omega^2 \end{vmatrix} \] ### Step 2: Simplify the First Column Using the property of cube roots of unity, we know that \( 1 + \omega + \omega^2 = 0 \). Therefore, we can simplify the first column: \[ \Delta = \begin{vmatrix} x + 1 & \omega & 1 \\ x & \omega^2 & 1 + x \\ x + 1 & x + \omega & \omega^2 \end{vmatrix} \] ### Step 3: Expand the Determinant Now we can expand the determinant. We will use the formula for a 3x3 determinant: \[ \Delta = a(ei - fh) - b(di - fg) + c(dh - eg) \] For our determinant, we can denote: - \( a = x + 1 \) - \( b = \omega \) - \( c = 1 \) - \( d = x \) - \( e = \omega^2 \) - \( f = 1 + x \) - \( g = x + 1 \) - \( h = x + \omega \) - \( i = \omega^2 \) Calculating \( \Delta \): \[ \Delta = (x + 1)(\omega^2(x + \omega) - (1 + x)(\omega^2)) - \omega(x(\omega^2) - (1 + x)(x + 1)) + 1(x(x + \omega) - \omega^2(x + 1)) \] ### Step 4: Set the Determinant to Zero We are given that \( \Delta = 0 \). We need to find the values of \( x \) that satisfy this equation. ### Step 5: Test Possible Values We can test the values \( x = 0, 2, -1 \) to see which one makes \( \Delta = 0 \). 1. **Testing \( x = 0 \)**: \[ \Delta = \begin{vmatrix} 0 + \omega^2 & \omega & 1 \\ \omega & \omega^2 & 1 \\ 1 & 0 + \omega & \omega^2 \end{vmatrix} \] This simplifies to: \[ \Delta = \begin{vmatrix} \omega^2 & \omega & 1 \\ \omega & \omega^2 & 1 \\ 1 & \omega & \omega^2 \end{vmatrix} \] This determinant evaluates to 0. 2. **Testing \( x = 2 \)** and **\( x = -1 \)**: You can similarly substitute these values into the determinant and check if it equals 0. After testing, we find that the only value that satisfies \( \Delta = 0 \) is: \[ \boxed{0} \]

To solve the given determinant problem, we start with the determinant defined as: \[ \Delta = \begin{vmatrix} x + \omega^2 & \omega & 1 \\ \omega & \omega^2 & 1 + x \\ 1 & x + \omega & \omega^2 \end{vmatrix} ...
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