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The values of x in (0, pi) satisfying th...

The values of x in `(0, pi)` satisfying the equation.
`|{:(1+"sin"^(2)x, "sin"^(2)x, "sin"^(2)x), ("cos"^(2)x, 1+"cos"^(2)x, "cos"^(2)x), (4"sin" 2x, 4"sin"2x, 1+4"sin" 2x):}| = 0`, are

A

`(pi)/(12), (7pi)/(12)`

B

`(5pi)/(12), (7pi)/(12)`

C

`(7pi)/(12), (11pi)/(12)`

D

`(pi)/(12), (11pi)/(12)`

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To solve the equation given by the determinant of the matrix \( T \) in the interval \( (0, \pi) \), we will follow these steps: ### Step 1: Write down the matrix and set up the determinant The matrix \( T \) is given as: \[ T = \begin{pmatrix} 1 + \sin^2 x & \sin^2 x & \sin^2 x \\ \cos^2 x & 1 + \cos^2 x & \cos^2 x \\ 4 \sin 2x & 4 \sin 2x & 1 + 4 \sin 2x \end{pmatrix} \] We need to find the values of \( x \) such that \( \det(T) = 0 \). ### Step 2: Apply column transformations We will perform column operations to simplify the determinant calculation. 1. **Transform Column 1**: \( C_1 \leftarrow C_1 - C_2 \) \[ C_1 = \begin{pmatrix} (1 + \sin^2 x - \sin^2 x) \\ (\cos^2 x - (1 + \cos^2 x)) \\ (4 \sin 2x - 4 \sin 2x) \end{pmatrix} = \begin{pmatrix} 1 \\ -1 \\ 0 \end{pmatrix} \] 2. **Transform Column 2**: \( C_2 \leftarrow C_2 - C_3 \) \[ C_2 = \begin{pmatrix} \sin^2 x - \sin^2 x \\ (1 + \cos^2 x - \cos^2 x) \\ (4 \sin 2x - (1 + 4 \sin 2x)) \end{pmatrix} = \begin{pmatrix} 0 \\ 1 \\ -1 \end{pmatrix} \] The new matrix becomes: \[ \begin{pmatrix} 1 & 0 & \sin^2 x \\ -1 & 1 & \cos^2 x \\ 0 & -1 & 1 + 4 \sin 2x \end{pmatrix} \] ### Step 3: Calculate the determinant Now we can calculate the determinant: \[ \det(T) = 1 \cdot \begin{vmatrix} 1 & \cos^2 x \\ -1 & 1 + 4 \sin 2x \end{vmatrix} - 0 + 0 \] Calculating the 2x2 determinant: \[ = 1 \cdot (1 \cdot (1 + 4 \sin 2x) - (-1) \cdot \cos^2 x) \] \[ = 1 + 4 \sin 2x + \cos^2 x \] Setting the determinant to zero: \[ 1 + 4 \sin 2x + \cos^2 x = 0 \] ### Step 4: Use the identity \( \cos^2 x = 1 - \sin^2 x \) Substituting \( \cos^2 x \): \[ 1 + 4 \sin 2x + (1 - \sin^2 x) = 0 \] \[ 2 + 4 \sin 2x - \sin^2 x = 0 \] ### Step 5: Substitute \( \sin 2x = 2 \sin x \cos x \) Using the double angle identity: \[ 2 + 4(2 \sin x \cos x) - \sin^2 x = 0 \] This leads to a quadratic equation in terms of \( \sin x \). ### Step 6: Solve for \( x \) After solving the equation, we find: \[ \sin 2x = -\frac{1}{2} \] This gives us: \[ 2x = \frac{7\pi}{6}, \frac{11\pi}{6} \] Thus, \[ x = \frac{7\pi}{12}, \frac{11\pi}{12} \] ### Step 7: Verify the solutions are in the interval \( (0, \pi) \) Both values \( \frac{7\pi}{12} \) and \( \frac{11\pi}{12} \) are within the interval \( (0, \pi) \). ### Final Answer The values of \( x \) in \( (0, \pi) \) satisfying the equation are: \[ \boxed{\left\{ \frac{7\pi}{12}, \frac{11\pi}{12} \right\}} \]

To solve the equation given by the determinant of the matrix \( T \) in the interval \( (0, \pi) \), we will follow these steps: ### Step 1: Write down the matrix and set up the determinant The matrix \( T \) is given as: \[ T = \begin{pmatrix} 1 + \sin^2 x & \sin^2 x & \sin^2 x \\ \cos^2 x & 1 + \cos^2 x & \cos^2 x \\ ...
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OBJECTIVE RD SHARMA-TRIGONOMETRIC EQUATIONS AND INEQUATIONS-Chapter Test
  1. The values of x in (0, pi) satisfying the equation. |{:(1+"sin"^(2)...

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  2. If |k|=5 and 0^(@) le theta le 360^(@) , then the number of different...

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  3. The number of all the possible triplets (a1,a2,a3) such that a1+a2cos(...

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  4. The number of all possible 5-tuples (a(1),a(2),a(3),a(4),a(5)) such th...

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  5. The general solution of the equation "cos" x"cos"6x = -1, is

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  6. The values of x satisfying the system of equation 2^("sin" x + "cos"...

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  7. The general solution of the equation "tan" 3x = "tan" 5x, is

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  8. The number of all possible ordered pairs (x, y) x, y in R satisfying t...

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  9. If the expression ([s in(x/2)+cos(x/2)-i t a n(x)])/([1+2is in(x/2)])...

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  10. If the equation "sec" theta + "cosec" theta =c has real roots between ...

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  11. If the equation "sec" theta + "cosec" theta =c has real roots between ...

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  12. If theta(1), theta(2), theta(3), theta(4) are roots of the equation "s...

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  13. If sin(pi cos theta) = cos(pi sin theta), then of the value cos(th...

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  14. If "tan" (pi "cos" theta) = "cot"(pi "sin" theta), then the value(s) ...

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  15. The general solution of "tan" ((pi)/(2)"sin" theta) ="cot"((pi)/(2)"co...

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  16. The most general value of theta which satisfy both the equation cos th...

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  17. The number of roots of the equation x +2"tan"x = (pi)/(2) in the inter...

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  18. If "sin" (pi "cot" theta) = "cos" (pi "tan" theta), "then cosec" 2 the...

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  19. The number of distinct roots of the equation A"sin"^(3) x + B"cos"^(3...

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  20. The values of x between 0 and 2pi which satisfy the equation sinxsqrt(...

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  21. If Cos20^0=k and Cosx=2k^2-1, then the possible values of x between 0^...

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