course mth 151

5.13. true

5. false

6. false

9. false

10. true

12. false

15. 1,2,4,5,10,36

18. 1,2,4,43,86,172

20. a,b,d,e,g,h

21.d

24. B,G

25. A- 7 is the greatest prime before you get to 10

B- 13

c- square root

D- Prime

27. 2 and three are and not there are no more because every other number is divisible by 2

30. the last four numbers digits are divisible by 16 2,320 = 145

33. 2 ^4 * 3 * 5

35. 2 ^3 * 2 ^ 3 * 5

36. 5 ^ 2 * 17

39. yes

40. yes

42. no

45. no

51. if it’s o, 2, 4, 6, 8

54. if it’s 0, 5

55. if it’s 0, 6

57. if it’s 6

63. no

65. yes

66. no

69. that’s not always true

70. the last digit is the same

72. A- 1763 B- 1847

75. A- 2 ^ 2 ^4 + 1 = 257

B- 251

80. it isn’t prime 30031 is divisiable by 59

81. 30031 = 59* 509 composite

84. no

85. n ^ p – 1