(ii) u=i+2j−k;v=−i+j+k;w=−π2i−πj+π2k\mathbf{u} = \mathbf{i} + 2\mathbf{j} - \mathbf{k}; \mathbf{v} = -\mathbf{i} + \mathbf{j} + \mathbf{k}; \mathbf{w} = -\dfrac{\pi}{2}\mathbf{i} - \pi\mathbf{j} + \dfrac{\pi}{2}\mathbf{k}u=i+2j−k;v=−i+j+k;w=−2πi−πj+2πk