The webpage https://tikzcd.yichuanshen.de provides a graphical interface to generate commutative diagrams. I find it extremely useful. More recently an even better tool was released! This is Quiver by Varkor, check out his blog: https://varkor.github.io/blog/2020/11/25/announcing-quiver.html

The relationship given in \ref{22} below (highlighted) is derived as follows: $$\vec{Z} = \vec{A} \cos(\theta) + \vec{B} \sin(\theta) \tag{1} \label{1}$$ With $ \vec{Z}, \vec{A}, \vec{B} \in \mathbb{C}$ as: $$\vec{A} = \alpha + j\delta \tag{2} \label{2}$$ $$\vec{B} = \beta + j\epsilon \tag{3} \la...