Hi one of my questions is the following:

sketch the graph of the function h : [1, 3] belonging to Real Numbers where:

h(t):= [(n+1)Sigma(j=1)] g(tj)x [tj, t{j-1}](t)

and x[tj, t{j-1}] is the characteristic function of the half open interval [tj, t{j-1})

Is there an easier way to explain all of this?