It is given that,
f: R → R is defined as f(x)={ 1, x>0 0, x=0 −1, x<1
Also, g: R → R is defined as g(x) = [x], where [x] is the greatest integer less than or equal to x.

Thus, when x ∈ (0, 1), we have fog(x) = 0 and gof (x) = 1.
Hence, fog and of do not coincide in (0, 1].