Today is our topic of discussion Concept of Trigonometry .
Concept of Trigonometry
The word Trigonometry has been derived from the words “Trigon’ and ‘Metry’. “Trigon’ is a Greek word which means three angles and ‘Metry’ means measure. In general Trigonometry means the measurement of three angles of a triangle. For practical purposes, trigonometry was introduced from for the measurement of three angle and three sides of a triangle and from their related ideas.
For example, the use of trigonometry in measuring the height of the tree with the help of its shadow, determining the width of a river by standing on its bank, determining the area of a triangular land etc. is very ancient and popular.
Besides, trigonometry is extensively used in every branches of mathematics and science. That is why trigonometry is well established as a very important topic in mathematics. Trigonometry has two branches; one is Plane Trigonometry, the other is Spherical Trigonometry. We are concerned with plane trigonometry only. After completing the chapter, the students will be able to –
- explain the concept of radian measurement;
- determine the relation between radian measurement and degree measurement;
- indicate trigonometrical ratios and their signs in the quadrant;
- find the trigonometrical ratios of standard angles and associated angles upto 2π;
- find the trigonometrical ratios of angle -Θ;
- find the trigonometrical ratios of angle nπ/2 and apply for integer n ≤4;
- solve simple trigonometrical equation.
See more: