The accompanying figure shows an "infinite staircase" con- structed from cubes. Find the total volume of the staircase, given that the largest cube has a side of length 1 and each successive cube has a side whose length is half that of the preceding cube. Figure Ex-22 In each part, find a closed form for the nth partial sum of the series, and determine whether the series converges. If so, find its sum. (a) in +in 2 + 1 (b) in in (-)-(-)+(-)- +in (k+1)² Use geometric series to show that (a) (-1)***=* 0 if -1<<1 10.4 infinite Series 671 (b)(x-3)= if 2<<4