Question
If $\vec{a}$ and $\vec{b}$ are unit vectors, what is the greatest value of $|\vec{a} + \vec{b}| + |\vec{a} - \vec{b}|$?
If $\vec{a}$ and $\vec{b}$ are unit vectors, what is the greatest value of $|\vec{a} + \vec{b}| + |\vec{a} - \vec{b}|$?