Answer:
see the explanation
Step-by-step explanation:
we have
![f(x)=x^2](https://tex.z-dn.net/?f=f%28x%29%3Dx%5E2)
This is the equation of a vertical parabola open upward
The vertex represent a minimum
The vertex is the point (0,0)
The general shape of a parabola is the shape of a "pointy" letter "u," or a slightly rounded letter, "v."
If the function is negative
then
![f(x)=-x^2](https://tex.z-dn.net/?f=f%28x%29%3D-x%5E2)
This is the equation of a vertical parabola open downward
The vertex represent a maximum
The vertex is the point (0,0)
see the attached figure to better understand the problem