http://gyazo.com/112bdb5beaeab7b60892897ad3b318c0

Question

kidrah69 · Answer

@dan815

thesmartone · Answer

He just finished one QH question, and now another one xD

dan815 · Answer

Here are some easy ways to see that matrix multiplication is not commutative

thesmartone · Answer

It does: http://prntscr.com/6x3ccm

anonymous · Answer

This is my first qualified helper question

thesmartone · Answer

Congrats

anonymous · Answer

why did you say i just asked one?

dan815 · Answer

First are you aware of how the inner dimensions of a matrix have to be equal so that a matrix multiplication is possisble :)

anonymous · Answer

let me just get an answer fam

dan815 · Answer

For example
Lets say we have 2 matrices
A and B
A is of dimension 2by3
B is of dimension  3by1

now A B is possible as 
2by3 * 3by1
        ^--- these inner dimensions are possible

However
BA is not possible since
3by1 * 2by3
         ^--- the inner dimensions make this multiplication impossible

dan815 · Answer

Now if u wanna see where the multiplication is possible!
and 
A * B = B * A then 

we have to multiple symmetric matrices

dan815 · Answer

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