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Sage Sky
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Hi
I have a question in my math coursework on matrices
Question is
Three matrices A, B and C are given by:
[tex]A = \begin{pmatrix} 2 & 5 \\ -4 & 1 \end{pmatrix} [/tex]
[tex]B = \begin{pmatrix} 1 & 3 \\ -2 & 6 \end{pmatrix}[/tex]
[tex]C = \begin{pmatrix} 2 & 1 \\ -3 & -1 \end{pmatrix}[/tex]
a) find the inverses of A and B
b) Solve the equation AXB=C
This is my solution
iknow have rearranged equation to make it
[itex]{X=}A\frac{C}{A B} [/itex]
i understand that you can't dived in matrices so i have to use the inverse of A and B
to make the equation [itex]{X=}{A}^{-1} {C} {B}^{-1} [/itex]
The det [itex]\left|A\right|[/itex] = 22
det [itex]\left|B\right|[/itex] = 12
[itex]A^{-1} = \frac{1}{22}[/itex] \begin{pmatrix} 1 & -5 \\ 4 & 2 \end{pmatrix}
[itex]B^{-1} = \frac{1}{12} [/itex] /begin{pmatrix} 6 & -3 \\ 2 & 1 \end{pmatrix}
and my answer for inv A mutliplied C is \frac{1}{22}[/itex] \begin{pmatrix} 17 & 6 \\ 2 & 2 \end{pmatrix} or \begin{pmatrix} 0.7727 & 0.2727 \\ 0.0909 & 0.0909\end{pmatrix}
and then i mutlipy by inv B i get matrix X= \begin{pmatrix} 0.4318 & -0.1705 \\ 0.0606 & -0.0152\end{pmatrix}
my question is this answer correct and how can i show the answer for Matrix X as [itex]X=\frac{1}{?} [/itex]\begin{pmatrix} a & b \\ c & d\end{pmatrix}
do i add the [itex]\frac {1}{22}+ \frac{1}{12} [/itex]which would make it [itex] \frac{1}{34} ?[/itex]
would this then make Matrix X [itex]X=\frac{1}{34} [/itex]\begin{pmatrix} a & b \\ c & d\end{pmatrix}
I have a question in my math coursework on matrices
Question is
Three matrices A, B and C are given by:
[tex]A = \begin{pmatrix} 2 & 5 \\ -4 & 1 \end{pmatrix} [/tex]
[tex]B = \begin{pmatrix} 1 & 3 \\ -2 & 6 \end{pmatrix}[/tex]
[tex]C = \begin{pmatrix} 2 & 1 \\ -3 & -1 \end{pmatrix}[/tex]
a) find the inverses of A and B
b) Solve the equation AXB=C
This is my solution
iknow have rearranged equation to make it
[itex]{X=}A\frac{C}{A B} [/itex]
i understand that you can't dived in matrices so i have to use the inverse of A and B
to make the equation [itex]{X=}{A}^{-1} {C} {B}^{-1} [/itex]
The det [itex]\left|A\right|[/itex] = 22
det [itex]\left|B\right|[/itex] = 12
[itex]A^{-1} = \frac{1}{22}[/itex] \begin{pmatrix} 1 & -5 \\ 4 & 2 \end{pmatrix}
[itex]B^{-1} = \frac{1}{12} [/itex] /begin{pmatrix} 6 & -3 \\ 2 & 1 \end{pmatrix}
and my answer for inv A mutliplied C is \frac{1}{22}[/itex] \begin{pmatrix} 17 & 6 \\ 2 & 2 \end{pmatrix} or \begin{pmatrix} 0.7727 & 0.2727 \\ 0.0909 & 0.0909\end{pmatrix}
and then i mutlipy by inv B i get matrix X= \begin{pmatrix} 0.4318 & -0.1705 \\ 0.0606 & -0.0152\end{pmatrix}
my question is this answer correct and how can i show the answer for Matrix X as [itex]X=\frac{1}{?} [/itex]\begin{pmatrix} a & b \\ c & d\end{pmatrix}
do i add the [itex]\frac {1}{22}+ \frac{1}{12} [/itex]which would make it [itex] \frac{1}{34} ?[/itex]
would this then make Matrix X [itex]X=\frac{1}{34} [/itex]\begin{pmatrix} a & b \\ c & d\end{pmatrix}
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