List of top Physics Questions on Unit Vectors

If \(\hat{n_1}, \hat{n_2}\)are two unit vectors and \(\theta\) is the angle between them, then \(\cos\frac{\theta}{2}\) is equal to

The unit vectors orthogonal to the vector\(-\hat{i}+2\hat{j}+2\hat{k}\) and making equal angles with the x and y axis is (are)