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If the maximum and minimum values of the...

If the maximum and minimum values of the determinant
`|(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 2x)|` are `alpha and beta`, then

A

`alpha + beta^(99) = 4`

B

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

C

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

D

a triangle can be constructed having its sides as `alpha, beta and alpha - beta`

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To solve the given determinant problem step by step, we can follow these steps: ### Step 1: Write the Determinant We start with the determinant given in the question: \[ D = \begin{vmatrix} 1 + \sin^2 x & \cos^2 x & \sin 2x \\ \sin^2 x & 1 + \cos^2 x & \sin 2x \\ \sin^2 x & \cos^2 x & 1 + \sin 2x \end{vmatrix} \] ### Step 2: Simplify the Determinant To simplify the determinant, we can perform column operations. We will add the first two columns together: \[ C_1 \rightarrow C_1 + C_2 \] This gives us: \[ D = \begin{vmatrix} (1 + \sin^2 x + \cos^2 x) & \cos^2 x & \sin 2x \\ (\sin^2 x + 1 + \cos^2 x) & 1 + \cos^2 x & \sin 2x \\ (\sin^2 x + \cos^2 x) & \cos^2 x & 1 + \sin 2x \end{vmatrix} \] Using the identity \(\sin^2 x + \cos^2 x = 1\), we can simplify further: \[ D = \begin{vmatrix} 2 + \sin^2 x & \cos^2 x & \sin 2x \\ 2 & 1 + \cos^2 x & \sin 2x \\ 1 & \cos^2 x & 1 + \sin 2x \end{vmatrix} \] ### Step 3: Expand the Determinant Now we can expand the determinant using the first row: \[ D = (2 + \sin^2 x) \begin{vmatrix} 1 + \cos^2 x & \sin 2x \\ \cos^2 x & 1 + \sin 2x \end{vmatrix} - \cos^2 x \begin{vmatrix} 2 & \sin 2x \\ 1 & 1 + \sin 2x \end{vmatrix} + \sin 2x \begin{vmatrix} 2 & 1 + \cos^2 x \\ 1 & \cos^2 x \end{vmatrix} \] ### Step 4: Calculate the 2x2 Determinants Now we calculate the 2x2 determinants: 1. \(\begin{vmatrix} 1 + \cos^2 x & \sin 2x \\ \cos^2 x & 1 + \sin 2x \end{vmatrix} = (1 + \cos^2 x)(1 + \sin 2x) - \sin 2x \cos^2 x\) 2. \(\begin{vmatrix} 2 & \sin 2x \\ 1 & 1 + \sin 2x \end{vmatrix} = 2(1 + \sin 2x) - \sin 2x = 2 + 2\sin 2x - \sin 2x = 2 + \sin 2x\) 3. \(\begin{vmatrix} 2 & 1 + \cos^2 x \\ 1 & \cos^2 x \end{vmatrix} = 2\cos^2 x - (1 + \cos^2 x) = 2\cos^2 x - 1 - \cos^2 x = \cos^2 x - 1\) ### Step 5: Substitute Back into the Determinant Substituting these back into the expression for \(D\): \[ D = (2 + \sin^2 x) \left[(1 + \cos^2 x)(1 + \sin 2x) - \sin 2x \cos^2 x\right] - \cos^2 x (2 + \sin 2x) + \sin 2x (\cos^2 x - 1) \] ### Step 6: Find Maximum and Minimum Values To find the maximum and minimum values of \(D\), we analyze the expression. The maximum value occurs when \(\sin^2 x\) and \(\cos^2 x\) take their maximum values, leading to: \[ \alpha = 3 \quad \text{(maximum)} \] And the minimum value occurs when these values are minimized, leading to: \[ \beta = 1 \quad \text{(minimum)} \] ### Final Result Thus, the maximum and minimum values of the determinant are: \[ \alpha = 3, \quad \beta = 1 \]
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OBJECTIVE RD SHARMA-DETERMINANTS-Exercise
  1. If alpha + beta + gamma = pi, then the value of the determinant |(e^...

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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. The repeated factor of the determinant |(y +z,x,y),(z +x,z,x),(x +y,...

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  4. The value of the determinant Delta = |((1 - a(1)^(3) b(1)^(3))/(1 - ...

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  5. The determinant Delta = |(b,c,b alpha +c),(c,d,c alpha + d),(b alpha...

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  6. Delta = |(1//a,1,bc),(1//b,1,ca),(1//c,1,ab)|=

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  7. If |(1 +ax,1 +bx,1 + bx),(1 +a(1) x,1 +b(1) x,1 + c(1) x),(1 + a(2) x,...

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  8. If a != 0, b!= 0, c!= 0, then |(1 +a,1,1),(1,1 +b,1),(1,1,1 +c)| is ...

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  9. If 1 + (1)/(a) + (1)/(b) + (1)/(c) = 0, then Delta = |(1 +a,1,1),(1,...

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  10. If a, b and c are all different from zero and Delta = |(1 +a,1,1),(1...

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  11. In a Delta ABC, a, b, c are sides and A, B, C are angles opposite to t...

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  12. If |(-12,0,lamda),(0,2,-1),(2,1,15)| = -360, then the value of lamda i...

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  13. If a(i), i=1,2,…..,9 are perfect odd squares, then |{:(a(1),a(2),a(3))...

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  14. If the maximum and minimum values of the determinant |(1 + sin^(2)x...

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  15. If [x] denote the greatest integer less than or equal to x then in ord...

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  16. If a, b gt 0 and Delta (x)= |(x,a,a),(b,x,a),(b,b,x)|, then

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  17. Let f(x) = ax^(2) + bx + c, a, b, c, in R and equation f(x) - x = 0 ha...

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  18. If g(x) = |(f(x + c),f(x + 2c),f(x + 3c)),(f(c),f(2c),f(3c)),(f(c),f'(...

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  19. If a^(2) + b^(2) + c^(2) = -2 and f(x) = |(1 + a^(2)x,(1 + b^(2))x,(1 ...

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  20. Coefficient of x in f(x)=|(x,(1+sinx)^3,cosx),(1,log(1+x),2),(x^2,(1+x...

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