Flashcards
Trigonometric Identities
Cards in this deck (26)
- 1csc x=1/sin x
- 2sec x=1/cos x
- 3cot x=1/tan x
- 4tan x=sin x /cos x
- 5cot x=cos x /sin x
- 6sin^2 x +cos^2 x =1
- 7tan^2 x +1 =sec^2 x
- 81 + cot^2 x=csc^2 x
- 9sin (-x)=-sin x
- 10cos (-x)=cos x
- 11tan (-x)=-tan x
- 12csc (-x)=-csc x
- 13sec (-x) =sec x
- 14cot (-x) =-cot
- 15sin (a+b) =sin a cos b +sin b cos a
- 16sin (a-b)=sin a cos b - sin b cos a
- 17cos (a+b)=cos a cos b - sin a sin b
- 18cos (a-b) =cos a cos b + sin a sin b
- 19tan (a+b) =tan a +tan b / 1-tan a tan b
- 20tan (a-b)=tan a - tan b / 1+ tan a tan b
- 21sin (2x)=2 sin x cos x
- 22cos (2x) =cos ^2 x - sin^2 x
- 23tan (2x) =2 tan x / 1-tan^2 x
- 24sin (x/2) =+-√(1-cos x)/2
- 25cos (x/2)=+-√(1+cos x)/2
- 26tan (x/2)=1-cos x/ sin x =sin x / 1+cos x