Given, f(x)=x−⌊x⌋csc−1x⇒f(x)={x}csc−1x For f(x) to be defined, {∣x∣≥1{x}>0⇒{x≤−1 or x≥1x=1 integers . i.e. x∈(−∞,−1]∪[1,∞)−{ integers i.e. all non-integers except the interval [−1,1] (here, −1 and 1 are included in except case, because of −1 and 1 are integers).