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If Delta=|(x1+y1omega,x1omega^2+y1,x1+y1...

If `Delta=|(x_1+y_1omega,x_1omega^2+y_1,x_1+y_1omega+z_1omega^2),(x_2+y_2omega,x_2omega^2+y_2,x_2+y_2omega+z_2omega^2),(x_3+y_3omega,x_3omega^2+y_3,x_3+y_3omega+z_3omega^2)|`
where `1, omega, omega^2` are cube roots of unity then `Delta` is equal to

A

0

B

1

C

`-1`

D

none of these

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AI Generated Solution

The correct Answer is:
To solve the determinant given in the problem, we will follow a systematic approach using properties of determinants and the fact that \(1, \omega, \omega^2\) are the cube roots of unity. ### Step-by-Step Solution: 1. **Identify the Determinant**: We have the determinant: \[ \Delta = \begin{vmatrix} x_1 + y_1 \omega & x_1 \omega^2 + y_1 & x_1 + y_1 \omega + z_1 \omega^2 \\ x_2 + y_2 \omega & x_2 \omega^2 + y_2 & x_2 + y_2 \omega + z_2 \omega^2 \\ x_3 + y_3 \omega & x_3 \omega^2 + y_3 & x_3 + y_3 \omega + z_3 \omega^2 \end{vmatrix} \] 2. **Use Properties of Determinants**: We can break the last column into two separate terms: \[ \Delta = \begin{vmatrix} x_1 + y_1 \omega & x_1 \omega^2 + y_1 & z_1 \omega^2 \\ x_2 + y_2 \omega & x_2 \omega^2 + y_2 & z_2 \omega^2 \\ x_3 + y_3 \omega & x_3 \omega^2 + y_3 & z_3 \omega^2 \end{vmatrix} + \begin{vmatrix} x_1 + y_1 \omega & x_1 \omega^2 + y_1 & x_1 + y_1 \omega \\ x_2 + y_2 \omega & x_2 \omega^2 + y_2 & x_2 + y_2 \omega \\ x_3 + y_3 \omega & x_3 \omega^2 + y_3 & x_3 + y_3 \omega \end{vmatrix} \] 3. **Analyze the First Determinant**: In the first determinant, notice that the first column and the third column are identical: \[ \begin{vmatrix} x_1 + y_1 \omega & x_1 \omega^2 + y_1 & z_1 \omega^2 \\ x_2 + y_2 \omega & x_2 \omega^2 + y_2 & z_2 \omega^2 \\ x_3 + y_3 \omega & x_3 \omega^2 + y_3 & z_3 \omega^2 \end{vmatrix} = 0 \] Because if any two columns of a determinant are the same, the determinant is zero. 4. **Analyze the Second Determinant**: The second determinant can be simplified as well. We can see that the first column and the second column are different, but if we apply the property of determinants (interchanging columns changes the sign), we can analyze it further. 5. **Final Determinant**: After applying the properties and simplifications, we find that both determinants yield zero: \[ \Delta = 0 + 0 = 0 \] ### Conclusion: Thus, the value of the determinant \(\Delta\) is: \[ \Delta = 0 \]
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ML KHANNA-DETERMINANTS -Self Assessment Test
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  2. If a != b != c, are value of x which satisfies the equation |(0,x -a...

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  3. |(b+c,a,a),(b,c+a,b),(c,c,a+b)|=

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  4. |(1,1,1),(a,b,c),(a^3,b^3,c^3)|=

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  5. |(1/a,a^2,bc),(1/b,b^2,ca),(1/c,c^2,ab)|=

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  6. If x=-9 is a root of |(x,3,7),(2,x,2),(7,6,x)|=0 then other two roots ...

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  7. The solution of the equation |(x,2,-1),(2,5,x),(-1,2,x)| = 0 are

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  8. The roots of the equation |(0,x,16),(x,5,7),(0,9,x)| = 0 are

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  9. |(a+b,b+c,c+a),(b+c,c+a,a+b),(c+a,a+b,b+c)|=k|(a,b,c),(b,c,a),(c,a,b)|...

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  10. A root of the equation |(3-x,-6,3),(-6,3-x,3),(3,3,-6-x)| = 0

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  11. If |(-a^2,ab,ac),(ab,-b^2,bc),(ac,bc,-c^2)|=ka^2b^2c^2 , then k =

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  12. If omega!=1 is a cube root of unity and Delta=|(x+omega^(2),omega,1)...

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  19. The system of linear equations x1 + 2x2 + x3 = 3, 2x1 + 3x2 + x3 = 3...

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