How do you solve the quadratic 3y^2+3y+1=0 using any method?

1 Answer
Dec 17, 2016

The answer is S={-1/2-isqrt3/6,-1/2+isqrt3/6}

Explanation:

If you have a quadratic equation

ax^2+bx+c=0

x=(-b+-sqrtDelta)/(2a)

Here our equation is

3y^2+3y+1=0

You calculate the discriminant

Delta=b^2-4ac

=9-4*3*1=-3

As, Delta<0, there are no solutions in RR but in CC

The solutions are

y=(-3+-sqrtDelta)/(2*3)=(-3+-isqrt3)/6

y_1=-1/2-isqrt3/6

and y_2=-1/2+isqrt3/6