Write a function that, given a vector of values from an unknown function, estimates the derivative at a given point by interpolating a quadratic polynomial through the closest 3 available points and differentiating the polynomial analytically.

Jackson, who works in the finance department of a company, is holding a seminar for other employees on how to file taxes. only three employees sign up to attend the seminar. which device can he use to share his presentation with a group of three employees?