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hali12
PLEASE HELP!!! Does anyone know how to do "Matrices" It's in algebra
\[spose:~A=(a_1~a_2)~and~B=\binom{b_1}{b_2}~then~AB=a_1b_1+a_2b_2\]
if we let A have so many Rows, and B have so many columns then: then AB is: \[Row_1.Col_1~~Row_1C.Col_2~~Row_1.Col_3\\ Row_2.Col_1~~Row_2C.Col_2~~Row_2.Col_3\\ Row_3.Col_1~~Row_3C.Col_2~~Row_3.Col_3\\ \]
To multiply A and B you can think of sending the rows of B into the columns of A by kind of rotating B counter clockwise. In your diagram, the result of AxB will be a 3x3 matrix as follows: (8*5 + 2*6), (0*5 + 6*6), (-3*5 + 4*6) (8*2 + 2*3), (0*2 + 6*3), (-3*2 + 4*3) (8*-4 + 2*0), (0*-4 + 6*0), (-3*-4 + 4*0)
Question (7) specifically, but the technique can be used in general and is what Amistre64 has stated quite nicely.