+6248 can you multiply two matrices together?
The top question wants you to multiply A times B, drag that to the box, then multiply that by C, and drag that product to the box.
The bottom question wants you to multiply B times C first, drag that into the box, then multiply A times that and put it in the box.
+128474 First one :
AB =
[7 1 ] * [ 1 -2 5 ] = [ 7*1 + 1*2 7*-2 + 1*4 7*5 + 1*1 ] = [ 9 -10 36 ]
[3 1 ] [2 4 1 ] [ 3*1 + 1*2 + 3*-2 + 1*4 3*5 + 1*1 ] [ 5 -2 16]
(AB)C =
[ 9 -10 36 ] * [ 2 ] = [ 9*2 + -10 * -1 + 36 * 0] = [ 28 ]
[ 5 -2 16] -1 [ 5*2 + -2*-1 + 16 * 0 ] [ 12 ]
[ 0 ]
And
BC = [1 -2 5 ] * [ 2 ] = [ 1*2 + -2*-1 + 5*0 ] = [ 4 ]
[ 2 4 1 ] -1 [ 2*2 + 4*-1 + 1*0 ] [ 0 ]
[ 0 ]
A(BC) = [7 1] * [ 4 ] = [ 7*4 + 1 * 0 ] = [ 28 ]
[3 1] [ 0] [ 3*4 + 1 * 0 ] [ 12 ]
