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If the max and values of Delta=|(1+sin...

If the max and values of
`Delta=|(1+sin^2x,cos^2x,sin2x),(sin^2x,1+cos^2x,sin2x),(sin^2x,cos^2x,1+sinx)|` and `alpha and beta` , then

A

`alpha +beta^(99) =4`

B

`alpha^3-beta^(17) =26`

C

`alpha^(2n)-beta^(2n)` is always an even integer for `n in N`

D

`EE` a triangle having sides as `alpha, beta and alpha -beta`

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To solve the problem, we need to find the maximum and minimum values of the determinant: \[ \Delta = \begin{vmatrix} 1 + \sin^2 x & \cos^2 x & \sin 2x \\ \sin^2 x & 1 + \cos^2 x & \sin 2x \\ \sin^2 x & \cos^2 x & 1 + \sin x \end{vmatrix} \] ### Step 1: Simplify the Determinant We can simplify the determinant by performing column operations. Let's add the first column and the second column together. \[ C_1 \to C_1 + C_2 \] This gives us: \[ \Delta = \begin{vmatrix} 1 + \sin^2 x + \cos^2 x & \cos^2 x & \sin 2x \\ \sin^2 x + 1 + \cos^2 x & 1 + \cos^2 x & \sin 2x \\ \sin^2 x + \cos^2 x & \cos^2 x & 1 + \sin x \end{vmatrix} \] Since \(\sin^2 x + \cos^2 x = 1\), we can simplify this further: \[ \Delta = \begin{vmatrix} 2 & \cos^2 x & \sin 2x \\ 2 & 1 + \cos^2 x & \sin 2x \\ 1 & \cos^2 x & 1 + \sin x \end{vmatrix} \] ### Step 2: Further Simplification Next, we can perform row operations. Let's subtract the first row from the second row and the first row from the third row: \[ R_2 \to R_2 - R_1 \] \[ R_3 \to R_3 - \frac{1}{2} R_1 \] This results in: \[ \Delta = \begin{vmatrix} 2 & \cos^2 x & \sin 2x \\ 0 & 1 + \cos^2 x - \cos^2 x & \sin 2x - \sin 2x \\ 0 & \cos^2 x - \frac{1}{2} \cos^2 x & 1 + \sin x - 1 \end{vmatrix} \] This simplifies to: \[ \Delta = \begin{vmatrix} 2 & \cos^2 x & \sin 2x \\ 0 & 1 & 0 \\ 0 & \frac{1}{2} \cos^2 x & \sin x \end{vmatrix} \] ### Step 3: Calculate the Determinant Now, we can calculate the determinant: \[ \Delta = 2 \cdot \begin{vmatrix} 1 & 0 \\ \frac{1}{2} \cos^2 x & \sin x \end{vmatrix} = 2 \cdot (1 \cdot \sin x - 0 \cdot \frac{1}{2} \cos^2 x) = 2 \sin x \] ### Step 4: Find Maximum and Minimum Values The maximum value of \(\sin x\) is \(1\) and the minimum value is \(-1\). Therefore: - Maximum value (\(\alpha\)): \[ \alpha = 2 \cdot 1 = 2 \] - Minimum value (\(\beta\)): \[ \beta = 2 \cdot (-1) = -2 \] ### Conclusion Thus, the maximum and minimum values are: \[ \alpha = 2, \quad \beta = -2 \]
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ML KHANNA-DETERMINANTS -Self Assessment Test
  1. If the max and values of Delta=|(1+sin^2x,cos^2x,sin2x),(sin^2x,1+co...

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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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  13. |((a^x+a^(-x))^2,(a^x-a^(-x))^(2),1),((b^x+b^(-x))^2,(b^x-b^(-x))^(2),...

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  14. The number of values of k which the linear equations 4x+ky+2z=0 kx...

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  15. The value of k for which the set of equationsx + ky + 3z=0, 3x + ky – ...

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  16. If x + y +z=0, 4x+3y -z=0 and 3x + 5y +3z=0 is the given system of equ...

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  17. The system of equations x + y + z=2, 3x – y +2z=6 and 3x + y +z=-18 ha...

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  18. The system of equations x+y+z=6, x+2y + 3z= 10, x+2y + lamdaz=mu has n...

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

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  20. Let a,b,c be such that b(a+c) ne 0 . If |(a,a+1,a-1),(-b,b+1,b-1),(c...

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