Question

what does it mean for which functions f is there a function g? what does this statement mean? Such sort of statements often appear in maths and always bounce over my head

Answer 1

Could you please be more specific. Is there an accompanying description of the functions f and g?

Answer 2

To just say "for which functions f is there a function g" makes no sense.

Answer 3

I think this means, given a certain set of constraints (function f) can function g produce an answer

Answer 4

if not, function g would produce an answer of undefined