Under "All Products", on the side, as a drop-down item.
It's a sore spot on a personal level for me. There are multiple back-stories behind it, but there are reasons (and a few benefits) why Mathcad has its own mathcad.com website.
PTC Marketer for Creo and Mathcad. I run their YouTube channels, some Creo campaigns, and all Mathcad campaigns and communications.