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(2x)
A
2 sin(x) cos(x)
4
Q
cos(2x)
A
cos^2 (x) − sin^2 (x)
2cos^2(x) - 1
1 - 2sin^2(x)
(1-tan^2(x)) / (1+ tan^2(x))
5
Q
sin(a + b)
A
sin(a) cos(b) + cos(a) sin(b)
6
Q
cos(a + b)
A
cos(a) cos(b) − sin(a) sin(b)
7
Q
Cot
A
1/tan = cos/sin
8
Q
Sec
A
1/cos
9
Q
Cosec
A
1/sin
