Multiplying Matricies

Multipling matricies is done very simpily. You can mutiply them by a single number or another matrix. There are two sets of rules to follow, one for each type of multiplication.

1.To multiply a matrix by another single number is very simple. You just take the number given and multiply each number in the matrix by that number. You must watch out for negartives for they can be tricky if not played close attention too.

2.To multiply another matrix you must make sure they match. The two inside number of the demensions side by have to be the same EX A*B B*C. The two outer numbers will be the demensions of your new matrix. EX A*B B*C (New demensions A*C). Then you mutliply each row by each column and add all sums. Then put into new matrix.

Ex1. 4*(9 3) = (32 12)
(0 -1) (0 -4)


Ex2. (2 0) * (1 5)
(3 4) (2 -1)
2(1)+0(2)=2
2(5)+0(-1)=10
3(1)+4(2)=15
3(5)+4(-1)=11
(2 10)
(15 11)