Ex 2.2, 2 - 3cos -1 x = cos-1 (4x3 - 3x) - Chapter 2 Class 12

Ex 2.2, 2 - Chapter 2 Class 12 Inverse Trigonometric Functions - Part 2

  1. Chapter 2 Class 12 Inverse Trigonometric Functions (Term 1)
  2. Serial order wise

Transcript

Ex 2.2, 2 3cosโˆ’1 ๐‘ฅ = cosโˆ’1 (4๐‘ฅ^3โˆ’ 3๐‘ฅ ), ๐‘ฅโˆˆ [1/2,1] Solving R.H.S cos^(โˆ’1) (4๐‘ฅ^3โˆ’ 3๐‘ฅ ) Putting x = cos ๐œƒ = cos^(โˆ’1) (4 ใ€–"cos" ใ€—^๐Ÿ‘๐œƒ โˆ’ 3cos ๐œƒ) = cos^(โˆ’1) (cos 3๐œƒ) = 3๐œƒ = 3 cos^(โˆ’1) x (cos 3x = 4 cos^3x โˆ’ 3 cos x) Now, x = cos ๐œƒ โˆด cos^(โˆ’1) (x) = ๐œƒ = L.H.S Hence, proved.

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.