Vector Algebra

The volume of parallelopiped, whose coterminous edges are given by \(\overline{\mathrm{u}}=\hat{\mathrm{i}}+\hat{\mathrm{j}}+\lambda \hat{\mathrm{k}}, \vec{v}=\hat{i}+\hat{j}+3 \hat{k}, \bar{w}=2 \hat{i}+\hat{j}+\hat{k}\) is 1 cu. units. If \(\theta\) is the angle between \(\bar{u}\) and \(\bar{w}\), then the value of \(\cos \theta\) is