Basic Trig Identities Flashcards
1
Q
sin^2 x + cos^2 x =
A
1
2
Q
tan^2 x + 1 =
A
sec^2 x
3
Q
sin(x + y) =
A
sin x cos y + cos x sin y
4
Q
cos(x + y) =
A
cos x cos y - sin x sin y
5
Q
sin 2x =
A
2 sin x cos x
6
Q
cos 2x =
A
cos^2 x - sin^2 x =
2 cos^2 x - 1 =
1 - 2 sin^2 x
7
Q
sin^2 x =
A
(1 - cos 2x)/2
8
Q
cos^2 x =
A
(1 + cos 2x)/2
9
Q
sin x/2 = sqrt((1 - cos x)/2)
A
cos x/2 = sqrt((1 + cos x)/2)
