0
423views
Examine whether the vectors X1 = [3 1 1], X2 = [2 0 -1], X3 = [4 2 1] are linearly independent.
1 Answer
0
3views

Matrix Equation

$k_1[3,1,1]+k_2[2,0,-1]+k_3[4,2,1]=0\\ 3k_1+2k_2+4k_3=0\\ 1k_1+0k_2+2k_3=0\\ k_1-k_2+k_3=0\\$ $\begin{bmatrix} 3&2&4 \ 1&0&2 \1&-1&1 \end{bmatrix} \begin{bmatrix}k_1\\ k_2\k_3\end{bmatrix}= \begin{bmatrix}0\\ 0\0\end{bmatrix} $   $R_{12}\\begin{bmatrix} 1&0&2 \ 3&2&4 \1&-1&1 \end{bmatrix} \begin{bmatrix}k_1\\ k_2\k_3\end{bmatrix}= \begin{bmatrix}0\\ 0\0\end{bmatrix} $ $R_2-3R_1,R_3-R_1\\\begin{bmatrix} 1&0&2 \\ 0&2&-2\\0&-1&-1 \end{bmatrix} \begin{bmatrix}k_1\\\ k_2\\k_3\end{bmatrix}= \begin{bmatrix}0\\\ 0\\0\end{bmatrix} $

$R_2+2R_1,\\\begin{bmatrix} 1&0&2 \\ 0&0&-2\\0&-1&-1 \end{bmatrix} \begin{bmatrix}k_1\\\ k_2\\k_3\end{bmatrix}= \begin{bmatrix}0\\\ 0\\0\end{bmatrix} \\ k_1 +2k_3=0\\ -2k_3=0\\ -k_2-k_3=0\\ solving \ the\ equation\\ k_1=0,k_2=0,k_3\\ Since\ all\ k_1,k_2,k_3 \ are\ zero\ the\ vectors \ are linearly\ independent$

Please log in to add an answer.