I don’t think ‘Accuracy’ is used much in math. https://mathworld.wolfram.com/Accuracy.html https://mathworld.wolfram.com/Accuracy.html exists, but I think it wo

I don’t think ‘Accuracy’ is used much in math. https://mathworld.wolfram.com/Accuracy.html https://mathworld.wolfram.com/Accuracy.html exists, but I think it would be better to report relative error (https://en.wikipedia.org/wiki/Approximation_error https://en.wikipedia.org/wiki/Approximation_error, https://mathworld.wolfram.com/RelativeError.html https://mathworld.wolfram.com/RelativeError.html), which is less than one in a million here. The math, in general, isn’t as good as it, IMO, should be. The claim “Thus, the interval [x₀, 2/x₀] envelopes √2. From this, it follows that the mid-point of the interval [x₀, 2/x₀] is a better approximation to √2” isn’t correct. The midpoint is a better approximation, but that doesn’t follow from “the interval [x₀, 2/x₀] envelopes √2.”. [1,999] envelopes √2, but 500 isn’t a better approximation of √2 than 1. (Aside: https://en.wikipedia.org/wiki/Accuracy_and_precision https://en.wikipedia.org/wiki/Accuracy_and_precision is useless for finding a definition of accuracy. The chapter “Common technical definition” doesn’t define anything, and the picture in that section seems to imply that, for both precision and accuracy, lower is better)