Help with d please, I have ten more minutes!!

In this problem you will calculate 2x dx by using the formal definition of the definite integral: (a) The interval [1, 4] is divided into n equal subintervals of length Ax. What is Ax (in terms of n)? Ac = 3 100 (b) The right-hand endpoint of the kth subinterval is denoted x*. What is x* (in terms of k and n)? 1+ 3k (c) Using these choices for * and Ax, the definition tells us that 2x da = lim [ flow )A= ] . What is f(x*) Ax (in terms of k and n)? f(x; ) Ax = 6(n+ 3k) n (d) Express _ f(x*) Ax in closed form. (Your answer will be in terms of n.) (e) Finally, complete the problem by taking the limit as n - oo of the expression that you found in the previous part. 2x dx = lim = 15