How to find the f(x) (least square method)

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The discussion revolves around finding the function f(x) using the least squares method to complete a data chart. The user provides a set of values for x, y, x^2, and xy but is unsure how to derive f(x). Respondents clarify that the provided values do not directly indicate a specific function and suggest searching online for examples of the least squares method. The user emphasizes their intention to complete the work independently, seeking only a memory jog. Overall, the conversation highlights the need for additional context or information to accurately determine f(x).
mjmara
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Hi my first post , I hope I chose the right forum?

I'm here looking for a memory jog not for someone to do my work, I'm trying to remember how to find the f(x) to complete this chart , there is many more data points but I'm just providing you with the top line , I shall do the rest myself, can someone help me please?
It's been many years since I attempted this problem :(


x y x^2 xy f(x) f(x)-y (f(x)-y)^2
________________________________________________
-8 6.8 64 -54.4 ?
 
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sorry

the format is all messed up

here

x___y___x^2___x.y____f(x)
-8__6.8__64____-54.4__?sorry for the format but this is the best I can do

x= -8
y= 6.8
x^2 = 64
x.y = -54.4
f(x) = ?
 
It still is not at all clear what you are asking. Yes, if x= -8 and y= 6.8, then x^2= 64 and xy= -54.4 but that has nothing to do with some function, "f". Do you have any other information?
 
mjmara said:
I'm here looking for a memory jog not for someone to do my work, I'm trying to remember how to find the f(x) to complete this chart
A google search on method of least squares will find some good examples for you to follow, if I have you right. Here is one that may help.
 
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