(adsbygoogle = window.adsbygoogle || []).push({}); 1. Find an equation that best fits the data?

Data

2 16.40

3 15.70

4 15.30

5 15.20

6 15.21

7 15.40

8 15.80

9 16.30

10 16.80

11 17.50

12 18.18

13 18.70

14 19.36

15 19.88

16 20.40

17 20.85

18 21.22

19 21.60

20 21.65

I have narrowed it down that it is most likely a cubic, because it seems to make sense.

I tried to use a matrix to solve this equation but found that it gave me a quartic, that did not match the data at all any help would be appreciated, is there a formula on how to solve cubics?

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# Trying to find the equation of a cubic

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