The functions f and g are given by f(x)={x} the fractional part of x and g(x)=12sin[x]π, where [x] denotes the integral part of x. Then range of gof is
[−1,1]
{0}
{−1, 1}
[0, 1]
(gof)(x)=g(f(x))=12sin[{x}]π=0, for all x ∈ R. Hence the range of gof is {0}.