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?