If u\mathbf{u}u and v\mathbf{v}v are non-zero vectors in R3\mathbb{R}^3R3 with u⋅v=∥u∥∥v∥\mathbf{u} \cdot \mathbf{v} = \|\mathbf{u}\|\|\mathbf{v}\|u⋅v=∥u∥∥v∥, what can you conclude?
They are orthogonal
They are anti-parallel (opposite directions)
They are parallel (same direction)
They are unit vectors