Lagrange interpolating polynomial

Theorem

Suppose $n$ points, then there is a unique polynomial $P(x)$ of degree $\leq n-1$ passing through the $n$ points, the Lagrange interpolating polynomial.

This may be found by #incomplete

References

1. https://mathworld.wolfram.com/LagrangeInterpolatingPolynomial.html
2. https://en.wikipedia.org/wiki/Lagrange_polynomial