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If equation x^2 tan^2 theta - (2 tan th...

If equation ` x^2 tan^2 theta - (2 tan theta ) x+1=0` and ` ((1)/(1+log_(b)ac))x^(2)+((1)/(a+log_(c)ab))x+((1)/(1+log_(a)bc)-1)=0` (where a,b,c , ` gt ` ) have a common root and than 2nd equation has equal roots , then number of possible value of ` theta ` in `(0,pi)` is

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To solve the problem, we need to analyze the two equations given and find the possible values of \( \theta \) in the interval \( (0, \pi) \). ### Step 1: Analyze the first equation The first equation is: \[ x^2 \tan^2 \theta - 2 \tan \theta \cdot x + 1 = 0 \] This is a quadratic equation in \( x \). For this equation to have a common root with the second equation, we need to determine the conditions under which it has roots. ### Step 2: Find the discriminant of the first equation The discriminant \( D \) of a quadratic equation \( ax^2 + bx + c = 0 \) is given by: \[ D = b^2 - 4ac \] For our equation: - \( a = \tan^2 \theta \) - \( b = -2 \tan \theta \) - \( c = 1 \) Thus, the discriminant becomes: \[ D = (-2 \tan \theta)^2 - 4(\tan^2 \theta)(1) = 4 \tan^2 \theta - 4 \tan^2 \theta = 0 \] Since \( D = 0 \), this implies that the first equation has equal roots. ### Step 3: Solve for the common root Since the first equation has equal roots, we can find the root using the formula: \[ x = \frac{-b}{2a} = \frac{2 \tan \theta}{2 \tan^2 \theta} = \frac{1}{\tan \theta} \] Let this common root be \( x_0 = \frac{1}{\tan \theta} \). ### Step 4: Analyze the second equation The second equation is: \[ \frac{1}{1 + \log_b(ac)} x^2 + \frac{1}{a + \log_c(ab)} x + \left(\frac{1}{1 + \log_a(bc)} - 1\right) = 0 \] For this equation to have equal roots, its discriminant must also be zero. ### Step 5: Find the discriminant of the second equation Let: - \( A = \frac{1}{1 + \log_b(ac)} \) - \( B = \frac{1}{a + \log_c(ab)} \) - \( C = \frac{1}{1 + \log_a(bc)} - 1 \) The discriminant \( D_2 \) of the second equation is: \[ D_2 = B^2 - 4AC \] Setting \( D_2 = 0 \) gives us the condition for equal roots. ### Step 6: Solve for \( \theta \) From the first equation, we found that: \[ \tan \theta = 1 \implies \theta = \frac{\pi}{4} \] Now, we need to check if there are other possible values of \( \theta \) in the interval \( (0, \pi) \). ### Step 7: Determine the number of solutions The function \( \tan \theta \) is equal to 1 at \( \theta = \frac{\pi}{4} \) and is periodic with a period of \( \pi \). However, within the interval \( (0, \pi) \), the only solution is: \[ \theta = \frac{\pi}{4} \] ### Final Answer Thus, the number of possible values of \( \theta \) in the interval \( (0, \pi) \) is: \[ \boxed{1} \]
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