Solution LI.C21 Robert Beezer
Theorem LIVRN says we can answer this question by putting theses vectors into a matrix as columns and row-reducing. Doing this we obtain, \begin{equation*} \begin{bmatrix} \leading{1} & 0 & 0\\ 0 & \leading{1} & 0\\ 0 & 0 & \leading{1}\\ 0 & 0 & 0 \end{bmatrix} \end{equation*} With $n=3$ (3 vectors, 3 columns) and $r=3$ (3 pivot columns) we have $n=r$ and the theorem says the vectors are linearly independent.