Question

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Am i correct?

7 (A hotaTion. Does +hat mean 23

Answer 1

$No~you~are~wrong.\\ Let~{\bf A}=\begin{bmatrix} a_{11} & a_{12} &a_{13} \\ a_{21}&a_{22} &a_{23} \\ a_{31}&a_{32} &a_{33} \\ a_{41}&a_{42} &a_{43} \end{bmatrix}=\begin{bmatrix} {\bf a}_1^T\\ {\bf a}_2^T\\ {\bf a}_3^T\\ {\bf a}_4^T \end{bmatrix}\\ where~{\bf a}_i^T=(a_{i1},a_{i2},~a_{i3})=ith~row~vector~of~A,~i=1,2,3,4.\\ When~A=\begin{bmatrix} 1 & 2&3 \\ 4&5 &6 \\ 7 & 8& 9 \end{bmatrix}\\ then~{\bf a}_1^T=(1,2,3),~{\bf a}_2^T=(4,5,6),~{\bf a}_3^T=(7,8,9).\\ \begin{bmatrix} 1 &4 & 7\\ 2 &5 & 8\\ 3&6 & 9 \end{bmatrix}~is~a~transpose~of~{\bf A}=\begin{bmatrix} 1 & 2&3 \\ 4&5 &6 \\ 7 & 8& 9 \end{bmatrix}.$