Linear Algebra and Its Applications · Problem 3.4.1
Orthogonality — Gilbert Strang
Mathematics · orthogonal-columns-least-squares
Problem
(a) Write the four equations for fitting y=C+Dt to the data
y=−4 at t=−2,y=−3 at t=−1y=−1 at t=1,y=0 at t=2.
Show that the columns are orthogonal.
(b) Find the optimal straight line, draw its graph, and write E2.
(c) Interpret the zero error in terms of the original system of four equations in two unknowns: The right-hand side (−4,−3,−1,0) is in the \_\_\_\_ space.