Page 93 - Numerical Analysis Using MATLAB and Excel

Chapter 3 Sinusoids and Phasors

π
cos 90° = cos --- = 0 (3.8)
2
2π – 1
cos 120° = cos ------ = ------ = – 0.5 (3.9)
3 2

5π – 3
cos 150° = cos ------ = ---------- = – 0.866 (3.10)
6 2

cos 180° = cos π = – 1 (3.11)

7π – 3
cos 210° = cos ------ = ---------- = – 0.866 (3.12)
6 2

5π – 2
cos 225° = cos ------ = ---------- = – 0.707 (3.13)
4 2

4π – 1
cos 240° = cos ------ = ------ = – 0.5 (3.14)
3 2
3π
cos 270° = cos ------ = 0 (3.15)
2

5π
cos 300° = cos ------ = 0.5 (3.16)
3
11π
cos 330° = cos --------- = 0.866 (3.17)
6

sin 0° = sin 360° = sin 2π = 0 (3.18)

π 1
-
sin 30° = sin --- = -- = 0.5 (3.19)
6 2
π 2
sin 45° = sin --- = ------- = 0.707 (3.20)
4 2
π 1
-
sin 60° = sin --- = -- = 0.866 (3.21)
3 2
π
sin 90° = sin --- = 1 (3.22)
2

2π 3
sin 120° = sin ------ = ------- = 0.866 (3.23)
3 2

3−6 Numerical Analysis Using MATLAB® and Excel®, Third Edition
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