"Four-digit mathematical tables" of Bradis, despite a large number of modern means of calculation of trigonometrical functions, do not go out of use. With their help it is possible to find quickly the necessary value, without making special efforts. But for this purpose it is necessary to learn to use these tables.
It is required to you
- - the set corner;
- - "Four-digit mathematical tables".
Instruction
1. Open "Four-digit mathematical tables. They are both in printing option, and on the Internet. Use them in both cases equally, only in the book it is necessary to glance in contents, and on the website — in the menu. Find the head "Sine" and open the necessary page.
2. Look what corner is given you. Bradis's tables can use and in case the corner fractional, that is is measured in degrees and minutes. If the size of a corner is given in radians, transfer it to degrees. It is equal to the work of the size in radians increased by the relation 180 ° on coefficient π and is expressed by a formula α1=α*180 °/π where α — corner size in degrees, and α1 — in radians.
3. In the table you see horizontal and vertical rows. Look at the most extreme row at the left. In the top left corner there is a word sin, and under it — a column of figures with designation of degree. This whole number of degrees. Find number which corresponds to number of the whole degrees in the coal set to you. For example, you were given a corner of 27 °18 in size'. Find number 27 in an extreme left column. Then in the top line find number 18. On crossing necessary a line and a column find the necessary value.
4. Pay attention that degrees in the table go in a row, and minutes — through six. That is 18 minutes can be found directly in the table, and 19 — no. To find a sine of the angle which number of minutes is not multiple to six there are amendments. They are in the right side of the table. Calculate a difference between the number of minutes in the set coal and the next where the number of minutes is multiple 6. If this difference makes 1, 2 or 3 minutes, just add on the necessary value to the last figure of size of a sine of a smaller corner. If the difference makes 4 or 5, take the size of the next bigger corner and take away value of the first or second amendments from the last figure.