These **video lectures** are basically prepared to provide the students a complete learning kit for IIT JEE examination preparation. It will help you to study each topic step by step. Like other JEE video lectures, this video will educate the IIT JEE aspirants about another interesting topic – **Trigonometric ratio.**

The first chapter in trigonometry is the **trigonometry ratio and identities**. Before starting this chapter on trigonometry, we must know about few of the important fundamental definitions such as angle.

What do you mean by the term angle? **In** **trigonometry**, we define angle as the mode of rotation made by straight line from one position to another. While understanding the term angle students will also be able to understand about initial line, positive angle and terminal line. Anticlockwise angel is positive and clockwise angle will be negative under trigonometry.

Trigonometry is purely based on concepts and one needs to be well acquainted with understanding the various fundamental definitions. In these JEE video lectures, student will practically learn as to what does the initial line, positive angle and terminal line means. Apart from this they will be able to see the diagrammatic view of various angels.

In trigonometry or otherwise as well you will know that there are total four quadrants, namely, the first quadrant, second quadrant, third quadrant and the fourth quadrant. Now when we take from x-axis to y-axis, which is in the first quadrant, the angel is defined by 90 degrees. Then in second quadrant, the angel is defined to be 180 degrees and so on. In the third quadrant, the value will be greater than 180 degrees but less than 270 degrees. Further, in last quadrant value will be more than 270 degrees but less than equal to 360 degrees. In this way, you will get the value of all the four quadrants respectively.

Now there are various unit of measurement of angle, such as radian, we can say that the entire span of 360 degrees is two pie radians. Now if we talk about degrees, then 1 degree is equal to 60 minutes.

Further, in this **Maths** **IIT JEE video lectures** you will study about all the trigonometric ratios in details. Apart from this students will understand the concept of perpendicular, base etc while understanding such concepts.