What is the minimum value of the function: f(x)=2x^2-10x+5?

Question

mimi_x3 · Answer

Have you differentiated it?

anonymous · Answer

No I have not. How do you do that?

mimi_x3 · Answer

do you know calculus?

anonymous · Answer

No I havent taken that class yet. This is AP Stats.

mimi_x3 · Answer

Statistics..? This is Calculus. Or is there an algebra method to solve this?

anonymous · Answer

This class is AP Stats but U guess it is just basic math review. (Algebra)

anonymous · Answer

I mean I

mimi_x3 · Answer

Hm, I don't know the algebra method..
maybe @lgbasallote might know

lgbasallote · Answer

i dont know algebra sorry

unklerhaukus · Answer

when the first derivative is zero, there will be a minimum or maximum

mimi_x3 · Answer

is the algebra method got to do something with the vertex (-b)/2a?

unklerhaukus · Answer

yes Mimi_x3, that formula will give us the x-coordinate of the vertex,

anonymous · Answer

um i am not sure, but i think if I use (-b)/2a the answer would be 5 or 2.5?

unklerhaukus · Answer

the value is the f(x),

so sub x=-b/2a  into f

f(-b/2a)=

to get the value of f(x) that the minimum

mimi_x3 · Answer

Vertex:
$$\large \left(-\frac{b}{2a},a\left(-\frac{b}{2a}\right)^{2}+b\left(-\frac{b}{2a}\right)+C\right)  $$
a> 0 => its a min
a<0 => its a max.

however, the calculus method is more nicer :)

anonymous · Answer

I got 2.5.i hope its right. thank you for helping.