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QUESTION

Solve the equation $x^2-4x+2=0$.

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ANSWER

$\ds x^2-4x+2=0,\hspace{1cm} x=\frac{4\pm\sqrt{(-4)^2-4(1)(2)}}{2}
=2\pm\frac{1}{2}\sqrt{8}=2\pm\sqrt{2}$


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