Hi there, I'm working on a problem right now that relates to least squares error estimate for polynomial fitting. I'm aware of techniques (iterative formulas) for finding the coefficients of a polynomial that minimizes the square error from a data set. So for example, for a data set that I believe is a first order polynomial, y(x) = a0 + a1*x, I have a method for finding the coefficients of a0 and a1. However, what if I were to make an assumption about one of the coefficients, specifically, let's says I want a0 = 0. The question is then, let's find y(x) = a1*x, such that a1 minimizes the square error. How would I go about solving this? The only method I know attempts to solve for a0 and a1, yet I'm making an assumption about a0 = 0, and am attempting to find a1. Does anyone know how to solve this problem? Or if there is a general solution to solve this? I believe the problem is really a calculus of variation problems, and I simply do not know the math. TLDR - What is the method for solving for polynomial coefficients (in a least squares sense), while being able to make assumptions about certain parameters.