Differential Equations and Linear Algebra (4th Edition)

Published by Pearson
ISBN 10: 0-32196-467-5
ISBN 13: 978-0-32196-467-0

Chapter 5 - Inner Product Spaces - 5.5 Chapter Review - Additional Problems - Page 376: 4

Answer

See below

Work Step by Step

Determine basic for rowspace $(A)$. $A=\begin{bmatrix} 1 & 2 &6\\ 2 & 1 & 6\\ 0 & 1 & 2\\ 1& 0 & 2 \end{bmatrix} \approx \begin{bmatrix} 1 & 2 &6\\ 0 & -3 & -6\\ 0 & 1 & 2\\ 0 & -2 & -4 \end{bmatrix} \approx \begin{bmatrix} 1 & 2 &6\\ 0 & 0 & 0\\ 0 & 1 & 2\\ 0& 0 & 0 \end{bmatrix}\approx \begin{bmatrix} 1 & 2 &6\\ 0 & 1 & 2\\ 0 & 0 & 0\\ 0& 0 & 0 \end{bmatrix}$ Hence, basic for rowspace $(A):\{(1,2,6),(0,1,2)\}$ Assume $x_1=(1,2,6)\\ x_2=(0,1,2)$ Apply Gram-Schmidt: $v_1=x_1=(1,2,6)\\ v_2=x_2-\frac{}{||v_1||^2}\\ =(0,1,2)-\frac{}{||(1,2,6||^2}(1,2,6)\\ =(0,1,2)-\frac{0.1+1.2+2.6}{||1^2+2^2+6^2}(1,2,6)\\ =(0,1,2)-\frac{14}{41}(1,2,6)\\ =\frac{1}{41}(-14,13,-2)$ To determine an orthogonal set, we obtain: $\frac{v_1}{||v_1||}=\frac{(1,2,6)}{\sqrt 1^2+2^2+6^2}=\frac{1}{\sqrt 41}(1,2,6)\\ \frac{v_2}{||v_2||}=\frac{\frac{1}{41}(-14,13,-2)}{\sqrt \frac{1}{41}.\frac{1}{41}.(-14)^2+13^2+(-2)^2}=\frac{1}{3\sqrt 41}(-14,13,-2)$ Determine basic for colspace $(A)$. $A=\begin{bmatrix} 1 & 2 &6\\ 2 & 1 & 6\\ 0 & 1 & 2\\ 1& 0 & 2 \end{bmatrix} \approx \begin{bmatrix} 1 & 2 &3\\ 2 & 1 & 3\\ 0 & 1 & 1\\ 1 & 0 & 1 \end{bmatrix} \approx \begin{bmatrix} 1 & 0 & 0\\ 2 & -3 & -3\\ 0 & 1 & 1\\ 1& -2 & -2 \end{bmatrix}\approx \begin{bmatrix} 1 & 0 &0\\ 2 & -3 & 0\\ 0 & 1 & 0\\ 1& -2 & 0 \end{bmatrix}$ The basic for colspace $(A):\{(1,2,0,1),(0,-3,1,-2)\}$ Assume $x_1=(1,2,0,1)\\ x_2=(0,-3,1,-2)$ Apply Gram-Schmidt: $v_1=x_1=(1,2,0,1)\\ v_2=x_2-\frac{}{||v_1||^2}\\ =(0,-3,1,-2)-\frac{}{||(1,2,0,1)||^2}(1,2,0,1)\\ =(0,-3,1,-2)-\frac{0.1+(-3).2+1.0+(-2).1}{||1^2+2^2+0^2+1^2}(1,2,0,1)\\ =(0,-3,1,-2)+\frac{4}{3}(1,2,0,1)\\ =\frac{1}{3}(4,-1,3,-2)$ To determine an orthogonal set, we obtain: $\frac{w_1}{||w_1||}=\frac{(1,2,0,1)}{\sqrt 1^2+2^2+0^2+1^2}=\frac{1}{\sqrt 6}(1,2,0,1)\\ \frac{w_2}{||w_2||}=\frac{\frac{1}{3}(4,-1,3,-2)}{\sqrt \frac{1}{3}.\frac{1}{3}.4^2+(-1)^2+3^2+(-2)^2}=\frac{1}{\sqrt 30}(4,-1,3,-2)$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.