Trig identities Flashcards
to identify the trig identities
1
Q
tan x (QI)
A
sin x/cos x
2
Q
cot x (QI)
A
cos x/ sin x
3
Q
sin x (RI)
A
1/ csc x
4
Q
cos x (RI)
A
1/ sec x
5
Q
tan x (RI)
A
1/ cot x
6
Q
cot x (RI)
A
1/ tan x
7
Q
sec x (RI)
A
1/ cos x
8
Q
csc x (RI)
A
1/ sin x
9
Q
sin^2 x + ______ = 1
A
cos^2 x
10
Q
sec^2 x + ______= 1
A
tan^2 x
11
Q
csc^2 x - ______= 1
A
cot^2 x
12
Q
sin (A ± B)
A
sin A cos B ± cos A Sin B
13
Q
cos (A ± B)
A
cos A cos B ± sin A sin B
14
Q
tan (A ± B)
A
Tan A ± tan B/ 1 tan(A) tan(B)
15
Q
sin (2θ)
A
2 sinθ cosθ
16
Q
cos (2θ)
A
cos^2 θ- sin^2 θ
2cos^2 θ -1
1- 2co^2 θ
17
Q
tan (2θ)
A
2tanθ/1- tan^2θ
18
Q
half angle
sin^2θ
A
1-cos(2θ)/2
19
Q
half angle
cos^2θ
A
1+cos(2θ)/2
20
Q
half angle
tan^2θ
A
1-cos(2θ)/1+cos(2θ)
21
Q
Sin A sin B
A
[cos (a-b) - cos (a+b)]/2
22
Q
Cos A cos B
A
[cos (a-b) + cos(a+b)]/2
23
Q
sin A cos B
A
[sin(a-b) + sin(a+b)]/2
24
Q
Cos A sin B
A
[sin (a-b) - sin(a+b)]/2
