== 2 1 3 (1 point) Let A 1 and b -3 2 6 The QR factorization of the matrix A is given by: 1 2 = ſ v2 ŠV2 0 V2 3 2 3 (a) Applying the QR factorization to solving the least squares problem Ax b gives the system: 3 wls, wie X = (b) Use backsubstitution to system in part (a) and find the least squares solution. =
(4.2) Let 4 7 A= 4 7 -2 1 (a) Find the QR decomposition of A. It has to be of the form A QR where Q is a 3 x 3 orthogonal matrix, and R is 3 x 2 upper-triangular. (b) Use part (a) to find the least squares solution to the -6 Ax -4 -2
Section 5.6 QR Factorization: Problem 6 Previous Problem Problem List Next Problem 2 9 (1 point) Let A = 1 1 and b = 6 The QR factorization of the matrix A is given by: 2 6 1 3 1 1 -ŠV2 V2 *V2 ܝܙܚܐܝ 0 (a) Applying the QR factorization to solving the least squares problem Ax = b gives the system: 3 X= 0 3 (b) Use backsubstitution to solve the system in part (a) and find the...
2 9 11 and b (1 point) Let A -6 The QR factorization of the matrix A is given by: 2 1 6 17 äv2 3 1 1 0 3 2 3 21 V2 3 áva (a) Applying the QR factorization to solving the least squares problem Ax b gives the system: X = 0 2 3 (b) Use backsubstitution to solve the system in part (a) and find the least squares solution. x=
T67 [21] (1 point) Let A = 1 1 and b = [21] -6 .The QR factorization of the matrix A is given by: 1-3] [21] [ 11 = [2 1 112] 2 -V2 ماده و V2 (a) Applying the QR factorization to solving the least squares problem Ax = b gives the system: (b) Use backsubstitution to solve the system in part (a) and find the least squares solution. 5/3 -3
Problem 6 (18 pts.): Let A be a 4 x 2 matrix given by: -1 -5 1 1 1 A= -1 -1 1 5 a) Compute the Gram-Schmidt QR factorization of A. b) Use the QR factorization to find the least squares solution of Az = 6, where 6= (-2,-1,5,0).
Problem #4: Let 0 2 A = 2 9 and b = 0 2 4 Find the least squares solution of the linear system Ax = b. Enter the components of the least squares solution x = [x y]? into the answer box below (in order), separated with a comma. Problem #4: Enter your answer symbolically, as in these examples Just Save Submit Problem #4 for Grading Problem #4 Attempt #1 Attempt #2 Attempt #3 Your Answer: Your Mark:
for the question, thanks for your help!
2. Let 2 -2 -11 1 3 S1 8 and b -2 -5 7 A= -4 5 2-9 18 Moreover, let A be the 4 x 3 matrix consisting of columns in S (a) (2.5 pt) Find an orthonormal basis for span(S). Also find the projection of b onto span(S) (b) (1.5 pt) Find the QR-decomposition of A. (c) (1 pt) Find the least square solution & such that |A - bl2 is...
Problem II. 1 (5 points). Let vi db Let A - ( Vy val, which is a 4 x 3 matrix. LA V - Spani. V vs). (1) Find the general least squares solution of Ax - b, with x - x 12 " ER (2) Calculate min{ lb - 2 :26V), the minimum value of b - z for all z EV. Hint. For part (2), you need to understand the significance of least squares solutions.
3. (25 pts) Consider the data points: t y 0 1.20 1 1.16 2 2.34 3 6.08 ake a least squares fitting of these data using the model yü)- Be + Be-. Suppose we want to m (a) Explain how you would compute the parameters β | 1 . Namely, if β is the least squares solution of the system Χβ y, what are the matrix X and the right-hand side vector y? what quantity does such β minimize? (b)...