Looking for interesting ways to represent trigonometric identities, I tried to connect the different symmetry formulas of cos, sin, tan and cotan.
For example, the cyan connection between π+x and x in the first column represents the equality cos(π+x) = -cos(x).
While making the image, I realized that it was similar to a synthesizer, more precisely a modular synthesizer. I also posted this image on r/synthesizers and received a lot of positive feedback and possible musical interpretations of an illustration.