Example 4 - If tan A = 1, then verify 2 sin A cos A = 1 - Proving

  1. Chapter 8 Class 10 Introduction to Trignometry
  2. Serial order wise
Ask Download

Transcript

Example 4 In a right triangle ABC, right-angled at B, if tan A = 1, then verify that 2 sin A cos A = 1. Finding AC by pythagoras theorem (Hypotenuse)2 = (Height)2 + (Base)2 AC2 = AB2 + BC2 Putting AB = BC = k AC2 = k2 + k2 AC2 = 2k2 AC = โˆš2๐‘˜2 AC = k โˆš2 We have to find 2 sin A cos A Substituting the value of sin A and cos A = 2 ร—1/โˆš2ร—1/โˆš2 = 2/(โˆš2 ร— โˆš2) = 2/(โˆš2 )^2 = 2/2 = 1

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.