33 trig identities

tan(-u) = [blank] u

- tan (even/odd)

cot(-u) = [blank] u

-cot (even/odd)

csc(-u)= = [blank] u

-csc (even/odd)

sin(-u) = [blank] u

-sin (even/odd)

tan^2x+ [blank] = sec^2x

1

sin2u=

2cosusinu

Identity derived from a triangle

Pythagorean Identity

sec u = 1 / [blank] u

cos

[blank] u = sin( pi/2 - u)

cos (cofunctions)

cos(-u) = [blank] u

cos (even/odd)

cot x = [blank] u / [blank] u

cos / sin

the only even functions

cos and sec

cos2u=

cos^2u-sin^2u

sin^2x+ [blank] x=1

cos^2x

cos(u-v)=

cosucosv+sinusinv

cos(u+v)=

cosucosv-sinusinv

tan u = 1 / [blank] u

cot

[blank] u = tan( pi/2 - u)

cot (cofunctions)

sin u = 1 / [blank] u

csc

[blank] u = sec( pi/2 - u)

csc (cofunctions)

1+ cot^2x = [blank] u

csc^2x

if u = u, use the

double angle formula

cos u = 1 / [blank] u

sec

[blank] u = csc( pi/2 - u)

sec (cofunctions)

sec(-u) = [blank] u

sec (even/odd)

csc u = 1 / [blank] u

sin

[blank] u = cos ( pi/2 - u)

sin (cofunctions)

tan x = [blank] u / [blank] u

sin / cos

sin(u+v)=

sinucosv+cosusinv

sin(u-v)=

sinucosv-cosusinv

cot u = 1 / [blank] u

tan

[blank] u = cot( pi/2 - u)

tan (cofunctions)

tan(u+v)=

tanu+tanv/1-tanutanv

tan(u-v)

tanu-tanv/1+tanutanv