In higher classes, we don’t use degree to measure angles

We use radians.

 

We define radian in terms of length of arc :

Angle subtended by an arc of 1 unit in a circle of radius 1 unit is 1 radian .

In other words,

  • If length of arc is 1 unit
  • & Radius = 1 unit
  • Then, angle at center = 1 radian

What is Radian.jpg

 

Note: In θ = l/r i.e. length of arc formula,

Angle is measured in radians

 

  1. Chapter 3 Class 11 Trigonometric Functions
  2. Concept wise

Transcript

In higher classes, we don’t use degree to measure angles We use radians. We define radian in terms of length of arc: Angle subtended by an arc of 1 unit in a circle of radius 1 unit is 1 radian. In other words, If length of arc is 1 unit & Radius = 1 unit Then, angle at center = 1 radian Note: In θ = l/r i.e. length of arc formula, Angle is measured in radians

About the Author

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.