Write the Word or Phrase That Best Completes Each Statement $A = \left[ \begin{array} { l } - 2 \\ 1 \\ - 1 \end{array} \right]$

Essay

Write the word or phrase that best completes each statement or answers the question.
-Let $A = \left[ \begin{array} { l } - 2 \\ 1 \\ - 1 \end{array} \right]$ and $B = \left[ \begin{array} { l l l } 1 & - 1 & 0 \end{array} \right]$
Find $\mathrm { AB }$ .