Question

Dado que :

A =

| 2 3 |
| 0 -1 |
|-1 4 |

e

B =

| 1 2 3|
|-2 0 4|

Determine A x B :

Answer 1

     Boa noite Optimistic

   A     B
  a,b  g,h,i 
  c,d  j,k,l 
  e,f     

AxB

l b*j+a*g,  b*k+a*h,  b*l+a*i l
l d*j+c*g,  d*k+c*h,  d*l+c*i l
l f*j+e*g,   f*k+e*h,   f*l+e*i l

   A
| 2 3 |
| 0 -1|
|-1 4 | 

    B
| 1 2 3|
|-2 0 4| 

a = 2, b = 3, c = 0, d = -1, e = -1, f = 4
g = 1, h = 2, i = 3, j = -2, k = 0, l = 4

  AxB

l -6 + 2, 0 + 4, 12 + 6l    l -4 , 4, 18 l
l 2 + 0 , 0 + 0, -4 + 0l  = l  2 , 0, -4 l
l -8 - 1 , 0 - 2, 16 - 3l      l -9 ,-2, 13 l