Finding Function for Set of Data?

Euphoriet
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Finding Function for Set of Data?

Anyone know how to find a function for a set of data (x and y table)... that make up a quadratic function (sort of like a part of a parabola)

I know I can do it in the calculator with QuadReg, but I woudl really appricaite it if someone could please walk me through the way in which you would do it algebraically.

Like if I had a sample set of data... how would I find the values for a, b and c in:


y= ax^2 + bx + c


I'm assuming that is the general formula typically used.
 
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Linear Algebra, least squares method.
 
That looks like what I need to do BUT, I have found no tutorial that I can understand... anyone care to give an example ... that simplifies this process
 
You need to take a course in linear alegbra.
 

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