Exercise 2.3.
Complete the second, third and fourth columns of table 2.1. Use a table of cosines (e.g. table 2.2), and/or a pocket calculator.
Table 2.1. Worksheet for exercise 2.1.
| i | i × 17° | cos(i × 17°) | 32000 × cos(i × 17°), rounded to the nearest whole number |
| 0 | 0° | 1.0000 | 32000 |
| 1 | 17° | 0.9563 | 30603 |
| 2 | 34° | 0.8291 | 26534 |
| 3 | 51° | 0.6296 | 20148 |
| 4 | 68° | 0.3751 | |
| 5 | 85° | 0.0878 | |
| 6 | 102° | -0.2070 | |
| 7 | 119° | -0.4839 | |
| 8 | 136° | -0.7185 | |
| 9 | 153° | -0.8904 | |
| 10 | 170° | ||
| 11 | |||
| 12 | |||
| 13 | |||
| 14 | |||
| 15 | |||
| 16 | |||
| 17 | |||
| 18 | |||
| 19 | |||
| 20 | |||
| 21 | 357° | ||
| 22 | 374° ( = 360° + 14°;
same as 14°) |
||
| 23 | 391° ( = 31°) | ||
| 24 | 408° ( = 48°) | ||
| 25 | 425° ( = 65°) | ||
| 26 | 442° ( = 82°) | ||
| 27 | 476° ( = 116°) |
Exercise 2.4.
Using e.g. 1 mm squared graph paper, plot 32000 × cos(i × 17°) on the shorter dimension against i on the longer dimension. Hint: use a scale of 500 units to 1 small square on the shorter dimension, i.e. 10 small squares = 5000 units, and 10 small squares to 1 unit on the longer dimension. Put 0 in the middle, with values in the range -35000 to +35000 below and above. Another way of phrasing this exercise is: sketch a cosine wave, taking samples at 17° intervals.