If α, β are roots of x2 – 3ax + a2 = 0, find the value(s) of a if α2 + β2 = 7 4 .

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 Given the quadratic equation \(x^2 - 3ax + a^2 = 0\), the sum and product of the roots \(\alpha\) and \(\beta\) are related to the coefficients of the quadratic equation:


\[ \alpha + \beta = 3a \]


\[ \alpha \beta = a^2 \]


We are also given that \(\alpha^2 + \beta^2 = 74\).


Now, let's express \(\alpha^2 + \beta^2\) in terms of the sum and product of the roots:


\[ \alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha \beta \]


Substitute the values from the given information:


\[ 74 = (3a)^2 - 2a^2 \]


\[ 74 = 9a^2 - 2a^2 \]


Combine like terms:


\[ 74 = 7a^2 \]


Now, solve for \(a\):


\[ 7a^2 = 74 \]


\[ a^2 = \frac{74}{7} \]


\[ a = \pm \sqrt{\frac{74}{7}} \]


Therefore, the values of \(a\) that satisfy the given condition are \(a = \sqrt{\frac{74}{7}}\) and \(a = -\sqrt{\frac{74}{7}}\).

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