If the vectors and are coplanar

MATHEMATICS · Subjective · CBSE · Mathematics · Vector Algebra · Vector Algebra

Problem

If the vectors

2 \boldsymbol{i} - \boldsymbol{j} + \boldsymbol{k}, \boldsymbol{i} + 2 \boldsymbol{j} - 3 \boldsymbol{k}

and

3 \boldsymbol{i} + a \boldsymbol{j} + 5 \boldsymbol{k}

are coplanar, then prove that

a = 4