(conic section) Find focus point given the equation of the parabola $ (3x^2-6x+2) $

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Judging by the picture, I don't think the focus point is correct, as it outside of the parabola.

I derived the coordinates of the parabola by first determining the a, b, and c value.

$$a=3, b=(-6), c=2$$

And then using the formula for the focus point:

$$F=(b/(2a), 1/(4a) + d/(4a))$$


Calculations

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What is the correct focus point?


EDIT:

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Better by differentiation with symbolic coefficients

$$ y= ax^2+bx+c;\, y^{'}=2ax+b ;\, y''=2a= 1/R $$ where $R$ is the radius of curvature, as $y^{'}=0$ in the curvature expression

The extremum point is

$$ (-b/2a, c-b^2/4a)$$ to whose $y$ coordinate we add $R/2=1/ 4a$ (sign automatically valid due to $a$ symbolically assigned ) to get $y$ coordinate of focal point as by virtue of a property of parabola its focal point bisects vertex-center of curvature line and this can be easily proved if we take parabola $ x^2= 4 f y.$ This gives us the formula for the focus.

$$ \boxed{(-b/2a,\, c+(1-b^2)/4a ) } $$

When $(a,b,c)=(3,-6,2)$ is plugged in, focal point coordinates are:

$$(1,-\frac{11}{12}). $$