College Trigonometry, 2011a

30 ◦ 1
10.2 The Unit Circle: Cosine and Sine 737
In Exercises 31 - 39, find all of the angles which satisfy the given equation.
31. sin(θ) = 1 2
√
3
32. cos(θ) =−
2
33. sin(θ) =0
34. cos(θ) =
√
2
2
35. sin(θ) =
√
3
2
36. cos(θ) =−1
37. sin(θ) =−1 38. cos(θ) =
√
3
2
39. cos(θ) =−1.001
In Exercises 40 - 48, solve the equation for t. (See the comments following Theorem 10.5.)
√
2
40. cos(t) = 0 41. sin(t) =−
2
42. cos(t) =3
43. sin(t) =− 1 2
44. cos(t) = 1 2
45. sin(t) =−2
√
2
46. cos(t) = 1 47. sin(t) = 1 48. cos(t) =−
2
In Exercises 49 - 54, use your calculator to approximate the given value to three decimal places.
Make sure your calculator is in the proper angle measurement mode!
49. sin(78.95 ◦ ) 50. cos(−2.01) 51. sin(392.994)
52. cos(207 ◦ ) 53. sin (π ◦ ) 54. cos(e)
In Exercises 55 - 58, find the measurement of the missing angle and the lengths of the missing sides.
(See Example 10.2.8)
55. Find θ, b, andc.
56. Find θ, a, andc.
c
θ
b
a
c
45 ◦ 3
θ