Let f(x) =| x |, g (x) =sin x
Df = R, Rf =[ 0, ∞ )
Dg =R, Rg=[–1,1]
∵ Rf. C Dg
∵ g o f is defined
and ( g o f) (x) =g(f(x)) =g(| x |)=sin| x |
Now f and g are both continuous for every x ∈ R.
∴ g o f i.e., sin | x | is continuous for every x ∈ R.