Riemann sum Ln and the right-endpoint Riemann sum Rn, of f(x) = x^ p-1
on the interval [1,b] for the uniform partition of [1,b] into n subintervals
of equal length ∆r = (b − 1)/n. Explain the summation formulas that you
are using, and compute the limit as n tends to ∞ of both Rn and Ln