If and make an acute angle,

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

Problem

\mathbf{a} = x\hat{i} + (x-1)\hat{j} + \hat{k}

and

\mathbf{b} = (x+1)\hat{i} + \hat{j} + a\hat{k}

make an acute angle,

\forall x \in \mathbb{R}

, then find the values of

a