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matrix multiplication:confused:

MATRIX One MATRIX 2

(−5−2−31\begin{matrix} -5 & -2 \\-3 & 1 \end{matrix} ) x (41)\begin{pmatrix} 4 \\ 1 \end{pmatrix}
(edited 12 years ago)
Reply 1
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TobeTheHero
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15
Thanks:smile:
Reply 2
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f1mad
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Original post by TobeTheHero
MATRIX One MATRIX 2

(−5−2−31\begin{matrix} -5 & -2 \\-3 & 1 \end{matrix} ) x (41)\begin{pmatrix} 4 \\ 1 \end{pmatrix}


If you have a general matrix:

(ABCD)\begin{pmatrix} A & B \\ C & D \end{pmatrix} * (EF)\begin{pmatrix} E \\ F \end{pmatrix}

=

((A∗E)+(B∗F)(C∗E)+(D∗F))\begin{pmatrix} (A*E) + (B*F) \\ (C*E) + (D*F) \end{pmatrix}

Does this help?
Reply 3
Avatar for TobeTheHero
TobeTheHero
OP
15
Original post by f1mad
If you have a general matrix:

(ABCD)\begin{pmatrix} A & B \\ C & D \end{pmatrix} * (EF)\begin{pmatrix} E \\ F \end{pmatrix}

=

((A∗E)+(B∗F)(C∗E)+(D∗F))\begin{pmatrix} (A*E) + (B*F) \\ (C*E) + (D*F) \end{pmatrix}

Does this help?


tons! Thank you:wink:
Reply 4
Avatar for f1mad
f1mad
13
Original post by TobeTheHero
tons! Thank you:wink:


Np.
Reply 5
Avatar for Fallen
Fallen
17
Original post by f1mad
Np.

Also remember that if you multiply an AxB and a BxC matrices together, you get an AxC matrix.

*and you can only multiply them together if the number of columns in the first is the same as the number of rows in the second.
(edited 12 years ago)

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