Recent content by Brutus

Great advice, I am following your suggestion, yesterday for example, I went to bed at 1830 and woke up at 0100(phone call). Today, I plan to stay awake until 2000, the good thing is that now I don't feel tired in the morning anymore :) . That might not be a bad idea. I can sleep just fine...

ok, thanks

Homework Statement Is the following true for matrices? Hypotesis: AB = AC A != 0(zero matrix) Thesis: B=C The Attempt at a Solution AB = AC AB - AC = 0(zero matrix) AB - AC = A(B-C) // using the following property: A(B+C) = AB + AC iff A is mn matrix and BC are np matrices...

Ok, I got it now. It is a line, the intersection of two planes, haha, boy I feel stupid now... Thanks.

Homework Statement Solve: \left\{ \begin{array} {ccc} 5x - y - z & = & 4 \\ x - y + 2z & = & -5 \end{array} \right. If the system has infinite solution, does it fill the entire space? The Attempt at a Solution I know the system is underdetermined since the number of variables is...

Great, thanks.

A paradox would be if you went back and killed your grandfather, otherwise it would be "just" a loop I think, but hey, when "mindsturbating", anything goes... :) I like to do this kind of things too once in a while, like what if the Universe/Cosmo/whatever behaves just like a sand clock, it...

Hi, I think I've some kind of serious sleep disorder, my sleeping hours are totally shifted, I usually go to bed when the sun goes up, at 0700-0900 and wake up at 1300-1600. It's really messing up with my life, I've skipped most of my classes this semester(to give you an idea, I only went...

Nevermind, I made a stupid mistake, in step 4 I did: row 3 - row 1 * 1/2 and forgot to write the -1/2 in A_{3 1} ... I also forgot to include the 5/2 in A_{4 1} when doing row 4 - row 1 * (-5/2) damn... I guess my mind was expecting a failure and it tricked itself into it...

Why am I not allowed to reuse rows to find the determinant via elementary operations? Hi, I am learning about matrices and determinants and there is something I can't figure out, straight to the point with an example: Evaluating the determinant... \begin{bmatrix} 1&2&3&4 \\ 5&6&7&8...