How do you derive a quadratic function given its table of values when there is no zero x value given?
For example,
x|1|2|3
y|-6|-3|4
I tried two methods in solving this but I can only get a. Any suggestions?
[Math] Deriving Quadratic Function Using Table of Values
quadratics
Best Answer
You know that $f(x)=ax^2+bx+c$ for suitable $a,b,c$. We are also given $$\begin{align}a+\hphantom{1}b+c&=f(1)=-6\\ 4a+2b+c&=f(2)=-3\\ 9a+3b+c&=f(3)=\hphantom{-}4\end{align} $$ That's three equations in three unknowns ...