Ex 3.3, 3 - Chapter 3 Class 11 Trigonometric Functions
Last updated at May 29, 2018 by Teachoo
Transcript
Ex 3.3, 3 Prove that cot2 /6 + cosec 5 /6 + 3 tan2 /6 = 6 Taking L.H.S. cot2 /6 + cosec 5 /6 + 3 tan2 /6 Putting = 180 = cot2( 180/60) + cosec( (5 180)/6) + 3 tan2(180/3) = cot2 30 + cosec (150 ) + 3tan2 30 Putting the values cot2 30 + cosec (150 ) + 3tan2 30 = ( 3)2 + 2 + 3 (1/ 3)^2 = 3 + 2 + 3 1/3 = 3 + 2 + 1 = 6 = R.H.S Hence proved
Finding Value of trignometric functions, given angle
Negative Angle Identities
Value of sin, cos, tan repeats after 2π
Shifting angle by π/2, π, 3π/2 , 2π
Example 8
Ex 3.2, 9 Important
Ex 3.2, 8 Important
Ex 3.2, 10
Example 9
Ex 3.2, 6
Ex 3.2, 7 Important
Example 10
Ex 3.3, 1
Ex 3.3, 2
Ex 3.3, 3 You are here
Ex 3.3, 4 Important
Ex 3.3, 8 Important
Ex 3.3, 9
Find values of sin 18, cos 18, cos 36, sin 36, sin 54, cos 54
Chapter 3 Class 11 Trigonometric Functions
Concept wise
- Radian measure - Conversion
- Arc length
- Finding Value of trignometric functions, given other functions
- Finding Value of trignometric functions, given angle
- (x + y) formula
- 2x 3x formula - Proving
- 2x 3x formula - Finding value
- cos x + cos y formula
- 2 sin x sin y formula
- Finding Principal solutions
- Finding General Solutions
- Sine and Cosine Formula
About the Author
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.