CSC 133 Discrete Structures Quiz Section 4.1

Name:__________________

  1. Write the first three terms of the sequence ci = (-1)i / 2i+1, for all integers i ³ 0.

    2. ½, -1/4, 1/8

  2. Compute the sequence .

    3. [(-1)3 –2] + [03 – 2] + [13 – 2] + [23 – 2]
    [-1 –2] + [– 2] + [-1] + [8 –2]
    0

  3. Write the sequence using summation or product notation.

    12 × (-22) × 32 × (-42) × 52 × (-62) × 72.



  4. Compute

    5. 7!/[5!(7 – 5)!] = 7(6)(5!)/[5!(2)!] = 7(6)/2 =7(3) = 21

  5. Use repeated division by 2 to convert (by hand) 103 from base 10 to base 2.

read | as "goes into"
0
2 | 1 r = 1
2 | 3 r = 1
2 | 6 r = 0
2 | 12 r = 0
2 | 25 r = 1
2 | 51 r = 1
2 | 103 r = 1
solution: (103)10 = (1100111)2
check: 26 + 25 + 22 + 21 + 20 = 64 + 32 + 4 + 2 + 1 = 103.