assuming the component is negative. You must also provide two angles for the antiparallel vector in the same order.

$\backslash$table$[[$Set$,A_x,|A_y|,,$Magnitude of $A,$Angle,,,Angle,,$],[5a,38,$ i$,83,62\mathrm{.}75,$~~$,(pos{A}_y),62\mathrm{.}75,x,(pos{A}_y)$