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If the difference of the roots of the equation `x^(2)-5x+6=0` is same as the difference of the roots of the equation `x^(2)+bx+c=0` then minimum value of `x^(2)+bx+c=0` is _________

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To solve the problem, we need to find the minimum value of the quadratic equation \(x^2 + bx + c = 0\) given that the difference of the roots of this equation is the same as the difference of the roots of the equation \(x^2 - 5x + 6 = 0\). ### Step 1: Find the difference of the roots of the first equation The first equation is: \[ x^2 - 5x + 6 = 0 \] For a quadratic equation \(ax^2 + bx + c = 0\), the difference of the roots can be calculated using the formula: \[ |\alpha - \beta| = \frac{\sqrt{D}}{a} \] where \(D = b^2 - 4ac\). Here, \(a = 1\), \(b = -5\), and \(c = 6\). Calculating \(D\): \[ D = (-5)^2 - 4 \cdot 1 \cdot 6 = 25 - 24 = 1 \] Now, substituting into the formula for the difference of the roots: \[ |\alpha - \beta| = \frac{\sqrt{1}}{1} = 1 \] ### Step 2: Set up the second equation The second equation is: \[ x^2 + bx + c = 0 \] For this equation, the difference of the roots is given by: \[ |\alpha_1 - \beta_1| = \frac{\sqrt{D'}}{1} = \sqrt{D'} \] where \(D' = b^2 - 4c\). Since we know that the difference of the roots is the same as the first equation, we set: \[ \sqrt{D'} = 1 \implies D' = 1 \] This gives us: \[ b^2 - 4c = 1 \] ### Step 3: Find the minimum value of the quadratic The minimum value of the quadratic \(x^2 + bx + c\) occurs at: \[ x = -\frac{b}{2a} = -\frac{b}{2} \] Substituting this back into the quadratic to find the minimum value: \[ \text{Minimum value} = \left(-\frac{b}{2}\right)^2 + b\left(-\frac{b}{2}\right) + c \] \[ = \frac{b^2}{4} - \frac{b^2}{2} + c \] \[ = \frac{b^2}{4} - \frac{2b^2}{4} + c = -\frac{b^2}{4} + c \] ### Step 4: Substitute \(c\) in terms of \(b\) From the equation \(b^2 - 4c = 1\), we can express \(c\) as: \[ c = \frac{b^2 - 1}{4} \] Substituting this into the minimum value expression: \[ \text{Minimum value} = -\frac{b^2}{4} + \frac{b^2 - 1}{4} \] \[ = -\frac{b^2}{4} + \frac{b^2}{4} - \frac{1}{4} = -\frac{1}{4} \] ### Final Answer Thus, the minimum value of \(x^2 + bx + c\) is: \[ \boxed{-\frac{1}{4}} \]
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