By "symbol functions for trigonometry," I think you meant the trigonometric functions. Here are the 3 basic trig functions:
And here are the other 3 trig functions (called reciprocal functions) and their definitions:
Each one also has its own inverse, which takes in the output of its original function and returns what the input would have been. It's written with a
You may also see it written as "arc-" and then the function name, for instance:
"Arc-" functions and inverse functions perform the same actions.
The 6 functions also have some different, more complicated properties and relationships. You should check out this link if you want to read more.