Question 43652
x^2-4x+2=0.
Plug the values of the coefficients into the quadratic formula:
a=+1
b=-4
c=+2
.
{{{x = (--4 +- sqrt( -4^2-4*1*2 ))/(2*1) }}}
.
Simplify:
{{{x = (4 +- sqrt( 16 -8 ))/(2) }}}
.
Continue to simplify:
{{{x = (4 +- sqrt( 8 ))/(2) }}}
.
The square root of 8 is 2sqrt2:
{{{x = (4 +- 2sqrt( 2 ))/(2) }}}
.
Factor out 2:

{{{x = 2(2 +- 1sqrt( 2 ))/(2) }}}
.
{{{x = (2 +- 1sqrt( 2 )) }}}