Provide an Appropriate Response $\mathbf { u }$ And $\mathbf { v }$

Provide an appropriate response.
-The unit vectors $\mathbf { u }$ and $\mathbf { v }$ are combined to produce two new vectors $\mathbf { a } = \mathbf { u } + \mathbf { v }$ and $\mathbf { b } = \mathbf { u } - \mathbf { v }$ . Show that $\mathbf { a }$ and $\mathbf { b }$ are orthogonal. Assume $\mathbf { u } \neq \mathbf { v }$ .