Linear algebra help

Question

Linear algebra help

abmon98 · Answer

attachment

abmon98 · Answer

[a11 a12 a13... ][x1
a21  a22 a23...   x2
a31 a23  a33...    x3
...    ....     .....     ....
The resulting matrix should be an m*1 matrix where a1x1+a12x2+a13x3....=0

abmon98 · Answer

equate to zero the 2nd and 3rd till the nth row.

ganeshie8 · Answer

Hint for part a : 

Choose $X$ from columns of the identity matrix $I_{n}$

abmon98 · Answer

Why should we use identity matrix in this case?

ganeshie8 · Answer

see if you can tell me why after using it

abmon98 · Answer

I think now i get you if I chose the matrix to be X=[1]
                                                     0
                                                      ..
then once AX, one entry of matrix in  each row will equal zero and therefore we can define A=0

abmon98 · Answer

part b) I would perform a transpose on both sides and its the same as in part a), right?

ganeshie8 · Answer

Looks good! http://eli.thegreenplace.net/2015/visualizing-matrix-multiplication-as-a-linear-combination/