Answer
The solution set is {$2-\sqrt 2, 2+\sqrt 2$}.
Work Step by Step
$x^2-4x+2=0$
$a=1, b=-4, c=2$
$D=b^2-4ac=(-4)^2-4\cdot1\cdot2=16-8=8>0$. The equation has two real solutions.
$x=\frac{-b\pm\sqrt {b^2-4ac}}{2a}=\frac{4\pm\sqrt 8}{2}$ Use quadratic formula.
$x=\frac{4\pm2\sqrt 2}{2}$ Simplify
$x=2\pm\sqrt 2$
$x=2+\sqrt 2$, $x=2-\sqrt 2$
The solution set is {$2-\sqrt 2, 2+\sqrt 2$}