Two Plus Two Newer Archives  

Go Back   Two Plus Two Newer Archives > Other Topics > Science, Math, and Philosophy
FAQ Community Calendar Today's Posts Search

Reply
 
Thread Tools Display Modes
  #11  
Old 04-25-2006, 07:56 PM
dirk dirk is offline
Member
 
Join Date: Oct 2005
Posts: 95
Default Re: Linear algebra, matrices, and you

[ QUOTE ]
If you regard all n-vectors as n x 1 matrices, then the dot product of two vectors, x and y, is just the matrix product, x^T y. This fact might be helpful.

[/ QUOTE ]

if you can't get it from this...
Reply With Quote
  #12  
Old 04-25-2006, 09:50 PM
TheHusky TheHusky is offline
Senior Member
 
Join Date: Nov 2005
Posts: 105
Default Re: Linear algebra, matrices, and you

in case noone has answered yet:

1) True: x.x is the length of the vector squared.

2) False: set all entries in C =0, A and B can then be any two matricies.

3)True: A=AI=ACB=IB=B

4) True: I assume by square you mean no. of rows = no. of columns, if so this is really obvious

Bonus:

(Ax) . (Ay) = (Ax)T (Ay) = xT AT A y = xT I y = xT y= x . y
Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 04:43 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.