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If `alpha` and `beta` are roots of equation `(log_(3)x)^(2)-4(log_(3)x)+2=0` then
The value of `log_(alpha)beta+log_(beta)alpha` is

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To solve the problem, we start with the given quadratic equation: \[ (\log_{3} x)^{2} - 4(\log_{3} x) + 2 = 0 \] Let \( y = \log_{3} x \). Then, we can rewrite the equation as: \[ y^{2} - 4y + 2 = 0 \] ### Step 1: Solve the quadratic equation We can use the quadratic formula to find the roots of the equation \( y^{2} - 4y + 2 = 0 \). The quadratic formula is given by: \[ y = \frac{-b \pm \sqrt{b^{2} - 4ac}}{2a} \] Here, \( a = 1 \), \( b = -4 \), and \( c = 2 \). Plugging in these values: \[ y = \frac{4 \pm \sqrt{(-4)^{2} - 4 \cdot 1 \cdot 2}}{2 \cdot 1} \] Calculating the discriminant: \[ b^{2} - 4ac = 16 - 8 = 8 \] Now substituting back into the formula: \[ y = \frac{4 \pm \sqrt{8}}{2} \] Since \( \sqrt{8} = 2\sqrt{2} \), we have: \[ y = \frac{4 \pm 2\sqrt{2}}{2} = 2 \pm \sqrt{2} \] Thus, the roots \( y_1 \) and \( y_2 \) are: \[ y_1 = 2 + \sqrt{2}, \quad y_2 = 2 - \sqrt{2} \] ### Step 2: Find \( \alpha \) and \( \beta \) Since \( y = \log_{3} x \), we can express \( x \) in terms of \( \alpha \) and \( \beta \): \[ \alpha = 3^{y_1} = 3^{2 + \sqrt{2}}, \quad \beta = 3^{y_2} = 3^{2 - \sqrt{2}} \] ### Step 3: Calculate \( \log_{\alpha} \beta + \log_{\beta} \alpha \) Using the change of base formula, we can express \( \log_{\alpha} \beta \) and \( \log_{\beta} \alpha \): \[ \log_{\alpha} \beta = \frac{\log_{3} \beta}{\log_{3} \alpha}, \quad \log_{\beta} \alpha = \frac{\log_{3} \alpha}{\log_{3} \beta} \] Now, we can calculate \( \log_{3} \alpha \) and \( \log_{3} \beta \): \[ \log_{3} \alpha = y_1 = 2 + \sqrt{2}, \quad \log_{3} \beta = y_2 = 2 - \sqrt{2} \] Substituting these into the expressions: \[ \log_{\alpha} \beta = \frac{2 - \sqrt{2}}{2 + \sqrt{2}}, \quad \log_{\beta} \alpha = \frac{2 + \sqrt{2}}{2 - \sqrt{2}} \] ### Step 4: Combine the two logarithmic expressions Now, we need to find: \[ \log_{\alpha} \beta + \log_{\beta} \alpha = \frac{2 - \sqrt{2}}{2 + \sqrt{2}} + \frac{2 + \sqrt{2}}{2 - \sqrt{2}} \] To simplify this, we will find a common denominator: \[ = \frac{(2 - \sqrt{2})^2 + (2 + \sqrt{2})^2}{(2 + \sqrt{2})(2 - \sqrt{2})} \] Calculating the numerator: \[ (2 - \sqrt{2})^2 = 4 - 4\sqrt{2} + 2 = 6 - 4\sqrt{2} \] \[ (2 + \sqrt{2})^2 = 4 + 4\sqrt{2} + 2 = 6 + 4\sqrt{2} \] Adding these: \[ (6 - 4\sqrt{2}) + (6 + 4\sqrt{2}) = 12 \] Calculating the denominator: \[ (2 + \sqrt{2})(2 - \sqrt{2}) = 4 - 2 = 2 \] Thus, we have: \[ \log_{\alpha} \beta + \log_{\beta} \alpha = \frac{12}{2} = 6 \] ### Final Answer The value of \( \log_{\alpha} \beta + \log_{\beta} \alpha \) is \( 6 \). ---
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