Английский язык
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- Бұл бет үшін навигация:
- EXERCISES: 1. Read the following words paying attention to the pronunciation
| TRIGONOMETRIC FUNCTIONS
Trigonometry is based on certain "functions" of angles. A function is a quantity that depends on another quantity for its value. Any quantity that depends upon an angle for its value is the function of that angle. If a right triangle is constructed, having a certain angle at one corner, there will be certain definite relations between the sides of this triangle. These ratios are six in number and are called the trigonometric functions. In any right triangle, we call the two lines that form the right angle the sides, while the line opposite the right angle is called the hypotenuse. One of two other sides is called opposite side, while the other is called the adjacent side. The ratio of the opposite side to the adjacent side is called the tangent of the angle. The ratio of the adjacent side to the opposite side is called the cotangent. In any right triangle, the sine of either acute angle is the ratio of the side opposite the angle to the hypotenuse. In any right triangle, the cosine of either acute angle is the ratio of the adjacent side to the hypotenuse. The secant of the angle is the reciprocal of the cosine, that is, it is reverse ratio of the cosine. In a right triangle, the secant of an angle is the ratio of the hypotenuse to the side adjacent to the angle. The cosecant is the reciprocal of the sine; that is there verse ratio, being the ratio of the hypotenuse to the side opposite the angle. EXERCISES: 1. Read the following words paying attention to the pronunciation: height, identify, satisfy, sine, cosine, combine, secant, cosecant, tangent, cotangent. 2. Add suffixes to the words given below and translate them into Russian: - wise: clock, counterclock, other; - tion: relate, opposite, abbreviate, definite; - ing: write, call, construct, shorten. 3. Make up sentences of your own using the words and expressions given below: to be based on, to depend on, for its value, is constructed, five in number, hypotenuse, opposite side, adjacent side. жүктеу/скачать 99.07 Kb. Достарыңызбен бөлісу:
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