I wonder how many degree of this curve where the endpoints are A0, A3, and A6?
Is it degree of 6?
The minimum degree polynomial, when given n points, is of degree n-1. You are given 7 points so the minimum fitting polynomial is of degree six.
Isn't this the maximum of the minimum degree polynomial that exactly fits n points? It's possible that the n points could be exactly fitted with a polynomial of lower degree.
You can use Lagrange interpolation to write down an explicit polynomial that passes through the given points. As the Wikipedia article notes, such a polynomial will be of minimum degree. However, what do you mean by saying that A3 is an endpoint?
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