Find all differentiable functions f : R ---> R such that (f composed f) = f.
R = All Real Numbers
(f composed f) = the function f composed with itself
f composed f = fof = f(f(x)
according to the question,
f(f(x)) = f(x)
What does this mean? => It implies that whatever is the value of function f at x, the same value ...
The diffrentiabilty of a given function is examined.