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Question 150294: Please Help!
The product of:
2 1
-3 5
and
3 1 -1
2 4 -2
all in brackets, is what?
Thank you for your time!: Please Help!
The product of:
2 1
-3 5
and
3 1 -1
2 4 -2
all in brackets, is what?
Thank you for your time!
Answer by Fombitz(1744) About Me  (Show Source):
You can put this solution on YOUR website!
In brackets, I'm assuming mean matrix notation.
A 2x2 matrix multiplied by a 2x3 matrix will produce a 2x3 matrix.
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(matrix(2,2,2,1,-3,5))(matrix(2,3,3,1,-1,2,4,-2))=(matrix(2,3,a,b,c,d,e,f))
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The rows of the first matrix are multiplied by the columns of the second matrix in this manner,
a=2*3+1*2=8
b=2*1+1*4=6
c=2*(-1)+1*(-2)=-4
d=(-3)*3+5*2=1
e=(-3)*1+5*4=17
f=(-3)*(-1)+5*(-2)=-7
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(matrix(2,2,2,1,-3,5))(matrix(2,3,3,1,-1,2,4,-2))=(matrix(2,3,8,6,-4,1,17,-7))