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If product of the real roots of the equation, `x^(2)-ax+30=2sqrt((x^(2)-ax+45)),agt0` is `lamda` minimum value of sum of roots of the equation is `mu`. The value of `(mu)` (where (.) denotes the least integer function) is

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To solve the given problem step by step, we start with the equation: \[ x^2 - ax + 30 = 2\sqrt{x^2 - ax + 45} \] ### Step 1: Rearranging the Equation Let \( y = x^2 - ax + 30 \). Then, we can rewrite the equation as: \[ y = 2\sqrt{y + 15} \] ### Step 2: Squaring Both Sides To eliminate the square root, we square both sides: \[ y^2 = 4(y + 15) \] ### Step 3: Simplifying the Equation Expanding the right side gives us: \[ y^2 = 4y + 60 \] Rearranging this leads to: \[ y^2 - 4y - 60 = 0 \] ### Step 4: Solving the Quadratic Equation Now we can solve the quadratic equation using the quadratic formula: \[ y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \( a = 1, b = -4, c = -60 \): \[ y = \frac{4 \pm \sqrt{(-4)^2 - 4 \cdot 1 \cdot (-60)}}{2 \cdot 1} \] Calculating the discriminant: \[ = \sqrt{16 + 240} = \sqrt{256} = 16 \] Thus, we have: \[ y = \frac{4 \pm 16}{2} \] Calculating the two possible values for \( y \): 1. \( y = \frac{20}{2} = 10 \) 2. \( y = \frac{-12}{2} = -6 \) (not valid since \( y \) must be non-negative) So, we take \( y = 10 \). ### Step 5: Substituting Back to Find \( x \) Now, substituting back to find \( x \): \[ x^2 - ax + 30 = 10 \] This simplifies to: \[ x^2 - ax + 20 = 0 \] ### Step 6: Finding the Product of Roots For the quadratic equation \( x^2 - ax + 20 = 0 \), the product of the roots \( \alpha \beta \) is given by: \[ \alpha \beta = \frac{c}{a} = 20 \] According to the problem, this product is equal to \( \lambda \), so \( \lambda = 20 \). ### Step 7: Finding the Sum of Roots The sum of the roots \( \alpha + \beta \) is given by: \[ \alpha + \beta = a \] ### Step 8: Applying the AM-GM Inequality Using the Arithmetic Mean-Geometric Mean (AM-GM) inequality: \[ \frac{\alpha + \beta}{2} \geq \sqrt{\alpha \beta} \] Substituting \( \alpha \beta = 20 \): \[ \frac{\alpha + \beta}{2} \geq \sqrt{20} \] Thus, \[ \alpha + \beta \geq 2\sqrt{20} = 4\sqrt{5} \] Calculating \( 4\sqrt{5} \): \[ \sqrt{5} \approx 2.236 \implies 4\sqrt{5} \approx 4 \times 2.236 \approx 8.944 \] ### Step 9: Finding the Minimum Value of \( \mu \) The minimum value of \( \alpha + \beta \) is \( 4\sqrt{5} \approx 8.944 \). Therefore, the least integer function \( \mu \) is: \[ \mu = \lfloor 8.944 \rfloor = 8 \] ### Final Answer Thus, the value of \( \mu \) is: \[ \boxed{8} \]

To solve the given problem step by step, we start with the equation: \[ x^2 - ax + 30 = 2\sqrt{x^2 - ax + 45} \] ### Step 1: Rearranging the Equation Let \( y = x^2 - ax + 30 \). Then, we can rewrite the equation as: \[ y = 2\sqrt{y + 15} \] ...
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