Do ( vec A + vec B) and (vec A-vec B) lien in the same plane. Explain.

Explanation

Yes , ` (vec A + vec B)` is represented by the diagonal of a parallelogram where two adjacent sides are represented by vectors ` vec A and vec B`. The diagonl passes therough the common tail of ` vec A and vec B`
(vec A-vec B) is represented by the other diaonal of the same parallelogram. If is not passing through the common tail of ` vec A and vec B`.
From above we note that both (vec A+ vec B), (vec A- vec B) lie in the plane of same parallelogram.