The projection of vector $\overrightarrow{AB}$ on the directed line $l$, if angle $\theta = \pi$ will be

The correct answer is $\overrightarrow{BA}$

Let the projection of vector $\overrightarrow{AB}$ on the directed line $l$ be $\overrightarrow{p}$

∴ $\overrightarrow{p}$ = $|\overrightarrow{AB}|$ $cos \theta$

=$|\overrightarrow{AB}|$ $cos \pi$

=$|\overrightarrow{AB}|$ $(-1)$

=$\overrightarrow{BA}$