TABLE OF CONTENTS Table 20.6 summarizes the values for the sine, cosine, and tangent functions of common angles. The triangles that yield these values are seen in Figures 20.54A, 20.54B, 20.55, and 20.56. Notice that the angles are given in degree and radian form. Radian measure is discussed in Chapter 7.
| Quadrant | I | II | III | IV | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ? (degrees) | 0 | 30 | 45 | 60 | 90 | 120 | 135 | 150 | 180 | 210 | 225 | 240 | 270 | 300 | 315 | 330 | 360 |
| ? (radians) | 0 | ?/6 | ?/4 | ?/3 | ?/2 | 2 ?/3 | 3 ?/4 | 5 ?/6 | ? | 7 ?/6 | 5 ?/4 | 4 ?/3 | 3 ?/2 | 5 ?/3 | 7 ?/4 | 11 ?/6 | 2 ? |
| sin ? | 0 | 1/2 | | | 1 | | | 1/2 | 0 | ?1/2 | | | ?1 | | | ?1/2 | 0 |
| cos ? | 1 | | | 1/2 | 0 | ?1/2 | | | ?1 | | | ?1/2 | 0 | 1/2 | | | 1 |
| tan ? | 0 | | 1 | | ? | | ?1 | | 0 | | 1 | | ? | | ?1 | | 0 |
The values are expressed as fractions with rationalized denominators. This table is useful to commit to memory.
When using a scientific calculator to find values for trigonometric functions, make sure the calculator is...
