Chapter 10 - NCPN

Practice and Problem Solving
Use a sum or difference identity to find the exact value of
each expression.
6. sin 150° 1 2
7. cos 120° – 1 2
8. tan 135° –1 9. cos 300° 1 2
10. tan 225° 1 11. cos 135° − 2
2
12. tan 15° 2− 3 13. sin 225° − 2
2
14. tan 105° − 3−2
15. sin 390° 1 2
16. cos 33° cos 27° – sin 33° sin 27° 1 2
17. sin 156° cos 66° – cos 156° sin 66° 1
18. cos 58° cos 13° + sin 58° sin 13°
2
2
19. sin 22° cos 8° + cos 22° sin 8° 1 2
tan31°+ tan 14°
20.
1− tan31° tan 14° 1
Write each expression as a trigonometric function of a single
angle measure.
21. sin 3θ cos 2θ + cos 3θ sin 2θ sin 5θ
22. cos 4θ cos 2θ – sin 4θ sin 2θ cos 6θ
23. sin 2θ cos θ – cos 2θ sin θ sin θ
24. cos 3θ cos θ + sin 3θ sin θ cos 2θ
25.
tan3θ
− tan θ
1+tan3θ
tan θ
tan 2θ
26. Use a graphing calculator to graph the function y = sin x and
y = (sin x + 30) on the same coordinate grid. Use the interval
0° ≤ x ≤ 360°.
a. Describe the graphs of the functions. see margin
b. For what value(s) of x in the interval 0° ≤ x ≤ 360° are the
functions equal x = 75°, 255°
10.7 Angle Sum and Difference Identities 477