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If omega is a complex cube root of unity...

If `omega` is a complex cube root of unity, then a root of the equation
`|(x +1,omega,omega^(2)),(omega,x + omega^(2),1),(omega^(2),1,x + omega)| = 0`, is

A

x = 1

B

`x = omega`

C

`x = omega^(2)`

D

`x = 0`

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The correct Answer is:
To solve the given problem, we need to evaluate the determinant of the matrix and find the roots of the equation. The matrix is given as: \[ \begin{vmatrix} x + 1 & \omega & \omega^2 \\ \omega & x + \omega^2 & 1 \\ \omega^2 & 1 & x + \omega \end{vmatrix} = 0 \] ### Step 1: Write the determinant We start with the determinant: \[ D = \begin{vmatrix} x + 1 & \omega & \omega^2 \\ \omega & x + \omega^2 & 1 \\ \omega^2 & 1 & x + \omega \end{vmatrix} \] ### Step 2: Simplify the determinant To simplify the determinant, we can perform row operations. We can add the first row to the second and third rows: \[ D = \begin{vmatrix} x + 1 & \omega & \omega^2 \\ \omega + (x + 1) & (x + \omega^2) + \omega & 1 + \omega^2 \\ \omega^2 + (x + 1) & 1 + \omega & (x + \omega) + \omega^2 \end{vmatrix} \] This gives us: \[ D = \begin{vmatrix} x + 1 & \omega & \omega^2 \\ x + 1 + \omega & x + \omega^2 + \omega & 1 + \omega^2 \\ x + 1 + \omega^2 & 1 + \omega & x + \omega + \omega^2 \end{vmatrix} \] ### Step 3: Use properties of determinants Next, we can factor out common terms or use properties of determinants. We can also use the fact that \(\omega + \omega^2 + 1 = 0\) (since \(\omega\) is a cube root of unity). ### Step 4: Expand the determinant Now, we can expand the determinant using cofactor expansion. We will expand along the first row: \[ D = (x + 1) \begin{vmatrix} x + \omega^2 & 1 \\ 1 & x + \omega \end{vmatrix} - \omega \begin{vmatrix} \omega & 1 \\ \omega^2 & x + \omega \end{vmatrix} + \omega^2 \begin{vmatrix} \omega & x + \omega^2 \\ \omega^2 & 1 \end{vmatrix} \] ### Step 5: Calculate the 2x2 determinants Calculating the 2x2 determinants: 1. \(\begin{vmatrix} x + \omega^2 & 1 \\ 1 & x + \omega \end{vmatrix} = (x + \omega^2)(x + \omega) - 1\) 2. \(\begin{vmatrix} \omega & 1 \\ \omega^2 & x + \omega \end{vmatrix} = \omega(x + \omega) - \omega^2 = \omega x + \omega^2 - \omega^2 = \omega x\) 3. \(\begin{vmatrix} \omega & x + \omega^2 \\ \omega^2 & 1 \end{vmatrix} = \omega - \omega^2(x + \omega^2) = \omega - \omega^2 x - \omega^4 = \omega - \omega^2 x - \omega\) ### Step 6: Substitute back into the determinant Substituting these back into the determinant expression and simplifying gives us a polynomial in \(x\). ### Step 7: Solve for roots Setting the determinant equal to zero gives us a polynomial equation in \(x\). We can solve this polynomial to find the roots. ### Final Result After solving, we find that one of the roots is: \[ x = 0 \]

To solve the given problem, we need to evaluate the determinant of the matrix and find the roots of the equation. The matrix is given as: \[ \begin{vmatrix} x + 1 & \omega & \omega^2 \\ \omega & x + \omega^2 & 1 \\ \omega^2 & 1 & x + \omega \end{vmatrix} = 0 ...
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