Reciprocal, quotient, double angle, and sum and difference Pre-Calculus Trigonometric Identities.
tan x (quotient identity)
(sin x)/(cos x)
cot x (quotient identity)
(cosx)/(sinx)
sin²x+cos²x
1
1 + cot²x
csc²x
1+tan²x
sec²x
cos(A + B)
cosAcosB - sinAsinB
cos(A - B)
cosAcosB + sinAsinB
sin(A + B)
sinAcosB + sinBcosA
sin(A - B)
sinAcosB - sinBcosA
sin x
1/(csc x)
csc x
1/(sin x)
cos x
1/(sec x)
sec x
1/(cos x)
tan x (reciprocal identity)
1/(cot x)
cot x (reciprocal identity)
1/(tan x)
sin(2x) (expanded)
sinxcosx + sinxcosx
sin (2x) (simplified)
2sinxcosx
cos(2x) (expanded)
cosxcosx - sinxsinx
cos(2x) (simplified with both sine and cosine)
cos²x - sin²x
cos(2x) (simplified with only sine)
1 - 2sin²x
cos(2x) (simplified with only cosine)
2cos²x - 1