My Math Forum LU-Decomposition

 Linear Algebra Linear Algebra Math Forum

August 21st, 2019, 10:43 PM   #1
Senior Member

Joined: Sep 2011

Posts: 102
Thanks: 1

LU-Decomposition

How do I solve (i)?
Attached Images
 1.jpg (20.1 KB, 12 views)

Last edited by skipjack; August 22nd, 2019 at 09:26 PM.

 August 22nd, 2019, 05:53 AM #2 Senior Member   Joined: Jun 2019 From: USA Posts: 213 Thanks: 90 Only A3 has a "proper" LU decomposition (without pivoting). Hopefully this much you had no problem with. As far as finding the decomposition, there are a number of algorithms you can find online. However, for 3x3 it is easy enough to solve on your own. $\displaystyle A=\begin{bmatrix} 1 & 0 & 0 \\ l_{2,1} & 1 & 0 \\ l_{3,1} & l_{3,2} & 1\end{bmatrix} \begin{bmatrix} u_{1,1} & u_{1,2} & u_{1,3} \\ 0 & u_{2,2} & u_{2,3} \\ 0 & 0 & u_{3,3} \end{bmatrix}$ Nine equations, nine unknowns.
 August 22nd, 2019, 07:52 PM #3 Senior Member   Joined: Sep 2011 Posts: 102 Thanks: 1 Thank you. I got it. How would I approach part (ii)?

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post ZMD Linear Algebra 1 February 18th, 2017 04:06 AM mick7 Linear Algebra 3 December 25th, 2013 10:00 AM Maor Linear Algebra 1 January 28th, 2012 08:47 PM Crouch Algebra 3 June 27th, 2011 11:14 AM rakeshkool27 Algebra 1 June 28th, 2010 03:25 AM

 Contact - Home - Forums - Cryptocurrency Forum - Top