(x)=-2x^2+2x+9 x-coordinate of the vertex
y- coordinate
symmetry
min max of f(x)
The value, f(1/2)=19/2 is Min or Max

Question

(x)=-2x^2+2x+9 x-coordinate of the vertex 
y- coordinate 
symmetry 
min max of f(x) 
The value, f(1/2)=19/2 is Min or Max

hero · Answer

Not sure if I fully understand what's going on here


19/2 should be the max if you did this right

anonymous · Answer

You can find the x-coord of the vertex of a parabola using the formula $$x=-b/2a = -2/2(-2) = -1/2$$

anonymous · Answer

He may have a typo.  why would the problem ask for f(+1/2) when the x-coordinate is x = /1/2?

hero · Answer

because x = 1/2, not -1/2

anonymous · Answer

Although it would still be a max (if the a = -2 is correct).

anonymous · Answer

I agree but that is what it says

anonymous · Answer

My fault! Sorry.

anonymous · Answer

Hero is correct (i made a sign error).  The vertex is a max because the orientation of the parabola is opening downward.  Evaluate the poly at x=1/2 to get the y-coordinate.

anonymous · Answer

y =f(1/2) = 18/2 = 9.5