Through these problems, express the given limit as a definite integral over the indicated interval [a,b]. Assuming that [xi-1,x] denotes the ith subinterval of a subdivision of [a,b] into n subintervals, all with the same length Δx = (b-a/n, and that mi =1/2(xi-1 + xi is the midpoint of the ith subinterval.

qqqqqqqqqqn

qqqlimqqqqqΣ (x^3-3xi^2 +1) Δx over [0,3]

qqqqn->∞qi=1

qqqqqqqqqqn

qqqlimqqqqqΣ (25-xi^2)^0.5 Δx over [0,5]

qqqn->∞qqi=1

Please show work and explain, I am very lost . Ignore the q's in the formulas.