📏 Vector length

==$|\vec{v}|=\sqrt{{\sum }_{i=1}^N{v}_i^2}$==

📖 Example:

1. $|\vec{v}|=|(2,3)|$
2. $|(2,3)|=\sqrt{(2^2+3^2)}$
3. $\sqrt{(2^2+3^2)}=\sqrt{13}$