1. In this problem be derive the formula: n i=1 n(n + 1) (2n + 1) 6 (a) Use the telescoping series method to write what [(1 + i)-i] converges to in terms of n. (b) Expand (Multiply out) the interior of the sum _[(1 + i) ] and then use summation n(n+1) properties and the fact that i = to reduce [(1 + i) i] so that the only 2 summations you have left are i. Zi=1 (c) Set the results of part a) to equal the results from part b) and solve for 1