Ex 3.3, 19 - Prove sin x + sin 3x / cos x  + cos 3x = tan 2x - cos x + cos y formula

  1. Chapter 3 Class 11 Trigonometric Functions
  2. Serial order wise
Ask Download

Transcript

Ex3.3, 19 Prove that sin x + sin 3x /( x + 3x ) = tan 2x Taking L.H.S. sin x + sin 3x /( x + 3x ) We solve sin x + sin 3x & cos x + cos 3x seperately Now + 3 / + 3 = (2 2x ( ) )/(2 2 ( ) ) = 2x /cos 2x = tan 2x = R.H.S Hence L.H.S = R.H.S Hence proved

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.