Learn All Concepts of Chapter 2 Class 11 Relations and Function - FREE. Check - Trigonometry Class 11 - All Concepts
We know from double angle formula that
These identities can also be used to reduce angles
Last updated at Dec. 4, 2018 by Teachoo
Learn All Concepts of Chapter 2 Class 11 Relations and Function - FREE. Check - Trigonometry Class 11 - All Concepts
We know from double angle formula that
These identities can also be used to reduce angles
Transcript
We know from double angle formula that sin 2x = 2 sin x cos x = 2 tan x / (1 + tan^2 x) cos 2x = cos^2 x - sin^2 x = 1 - 2 sin^2 x = 2 cos^2 x - 1 = 1 - tan^2 x / 1 + tan^2 x tan 2x = 2 tan x / (1 - tan^2 x) These identities can also be used to reduce angles sin x = 2 sin x/2 cos x/2 = 2 tan x/2 / (1 + tan^2 x/2) cos x = cos^2 x/2 - sin^2 x/2 = 1 - 2 sin^2 x/2 = 2 cos^2 x/2 - 1 = 1 - tan^2 x/2 / 1 + tan^2 x/2 tan x = 2 tan x/2 / (1 - tan^2 x/2)
About the Author