Question 381064
OK
Using the quadratic formula:
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}

Now when b^2-4ac<0, the quadratic will have imaginary roots, so:
(-2)^2-4*3*k<0 
4-12k<0
-12k<-4 0r
12k>4
k>1/3

Hope this helps---ptaylor