We have 2 x 2 +x+1=0 .
Any equation of the form a x 2 +bx+c=0 has the solution
x= −b± D 2a
Here, D= b 2 −4ac is called the discriminant of the quadratic equation.
Therefore,
x= −1± 1 2 −4×2×1 2×2 = −1± −7 4 = −1± 7 i 4
Thus, x= −1± 7 i 4
6x^2-x-2=0 , x=-1/2,2/3