Trig Identities Flashcards
1
Q
1 = (sin)
A
Sin^2 θ + cos^2 θ
2
Q
1 = (cos)
A
Sin^2 θ + cos^2 θ
3
Q
1 = (sec)
A
Sec^2 θ - tan^2 θ
4
Q
1 = (tan)
A
Sec^2 θ - tan^2 θ
5
Q
1 = (csc)
A
Csc^2 θ - cot^2 θ
6
Q
1 = (cot)
A
Csc^2 θ - cot^2 θ
7
Q
Cos θ
A
Sin(pi/2 - θ)
8
Q
Cot θ
A
Tan(pi/2 - θ)
9
Q
Sec θ
A
Csc(pi/2 - θ)
10
Q
Sin θ
A
Cos(pi/2 - θ)
11
Q
Tan θ
A
Cot(pi/2 - θ)
12
Q
Csc θ
A
Sec(pi/2 - θ)
13
Q
Sin(2θ)
A
2sinθ cosθ
14
Q
Cos(2θ) (cos &sin)
A
Cos^2 θ - sin^2 θ
15
Q
Cos(2θ) (cos)
A
2cos^2 θ -1
16
Q
Cos(2θ) (sin)
A
1-2sin^2 θ
17
Q
Tan(2θ)
A
(2 tanθ)/(1-tan^2 θ)
18
Q
Sin(θ/2)
A
±√((1-cos θ)/2)
19
Q
Cos(θ/2)
A
±√((1+cos θ)/2)
20
Q
Tan(θ/2) (cos only)
A
±√((1-cos θ)/(1+cos θ))
21
Q
Tan(θ/2) (sin & cos)
A
(Sin θ)/(1+cos θ)
22
Q
Sin^2 θ
A
(1-cos(2θ))/2
23
Q
Cos^2 θ
A
(1+cos(2θ))/2
24
Q
Tan^2 θ
A
(1-cos(2θ))/(1+cos(2θ)
25
Q
Sin(θ ± α)
A
Sin θ cos α ± cos θ sin α
26
Q
Cos(θ ± α)
A
Cos θ cos α ∓ sin θ sin α
