1. Yes, when the reference angle is 4π and the terminal side of the angle is in quadrants I and III. Thus, at x=4π,45π, the sine and cosine values are equal.
3. Substitute the sine of the angle in for y in the Pythagorean Theorem x2+y2=1. Solve for x and take the negative solution.
5. The outputs of tangent and cotangent will repeat every π units.
7. 323
9. 3
11. 2
13. 1
15. 2
17. 33
19. −323
21. 3
23. −2
25. −1
27. −2
29. −33
31. 2
33. 33
35. −2
37. −1
39. If sint=−322,sect=−3,csct=−432,tant=22,cott=42
41. sect=2,csct=323,tant=3,cott=33
43. −22
45. 3.1
47. 1.4
49. sint=22,cost=22,tant=1,cott=1,sect=2,csct=2
51. sint=−23,cost=−21,tant=3,cott=33,sect=−2,csct=−323
53. –0.228
55. –2.414
57. 1.414
59. 1.540
61. 1.556
63. sin(t)≈0.79
65. csct≈1.16
67. even
69. even
71. costsint=tant
73. 13.77 hours, period: 1000π
75. 7.73 inches