Find the exact values of the cosine and sine of each angle. Then find the decimal values. Round your answers to the nearest hundredth. See Problems 4 and 5.

26. 
27. 
28. 
29. − 240 ° negative 240 degrees
30. 390°
31. 315°
32. − 30 ° negative 30 degrees
33. − 225 ° negative 225 degrees

B Apply

Graphing Calculator For each angle θ, find the values of cos θ and sin θ. Round your answers to the nearest hundredth.

34. − 95 ° negative 95 degrees
35. − 10 ° negative 10 degrees
36. 154°
37. 90°
38. 210°
39. Think About a Plan On an analog clock, the minute hand has moved 128° from the hour. What number will it pass next?
    • How can a drawing help you understand the problem?
    • How can you find the number of degrees between every two consecutive numbers?

Open-Ended Find a positive and a negative coterminal angle for the given angle.

40. 45°
41. 10°
42. − 675 ° negative 675 degrees
43. 400°
44. 213°

Determine the quadrant or axis where the terminal side of each angle lies.

45. 150°
46. 210°
47. 540°
48. − 60 ° negative 60 degrees
49. 0°
50. Time The time is 2:46 P.M. What is the measure of the angle that the minute hand swept through since 2:00 P.M.?

51. 1. Copy and complete the chart below.

       
       Image Long Description

    2. Suppose you know that cos θ is negative and sin θ is positive. In which quadrant does the terminal side of the angle lie?
    3. Writing Summarize how the quadrant in which the terminal side of an angle lies affects the sign of the sine and cosine of that angle.
52. 
    1. Graphing Calculator Use a calculator to find the value of each expression: cos 40°, cos 400°, and cos ( − 320 ° negative 320 degrees ).
    2. Reasoning What do you notice about the values you found in part (a)? Explain.

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