The matrix product is just a matter of definition:
So
See the pattern?
You do BA. I get
-Dan
Hello, Amanda!
We have: . .[1](b) Write the system: . . in matrix form: .
Use the inverse matrix method to solve the system for and .
I assume we are to find the inverse of matrix . . . ack!
We have: .
. .
. .
. .
Hence: .
Left-multiply both sides of [1] by
. .
. .
. .
Therefore: .
. . (I need a nap!)
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Any other method (Elimination, Substitution, Cramer's Rule,
. . Augmented Matrix) would have been much shorter.