I noticed if I type
sin[x] cos[x] and hit Shift+Return to run it in the Mathematica 12 frontend notebook, a grey '×' character is printed between the functions.
But, if I type
Sin[x] Cos[x]and hit Shift+Return, no such character appears
What are the rules that govern whether or not the '×' is printed? And can they be modified for user-defined symbols?