If h(x) = g(x) + f(x) is a continuous function in a given interval then g(x) and f(x) individually will also be continuous in the same interval.
When we deal with algebra of continuous functions always keeps I mind that this relation is true only in reverse i.e., if f(x) and g(x) are continuous at a point or interval then f+g,f−g,f.g,fg(g≠0) are also continuous. But the reverse is not true.
We can have examples which can show this.
h(x)=x;
g(x)=1x
f(x)=x−1x
here
h(x)=g(x)+f(x) is continuous at every x ϵ R but f(x) and g(x) individually taken are not continuous throughout as they are discontinuous at x=0.