trignometry Flashcards
(11 cards)
1
Q
sin(x+y
A
sinxcosy±cosxsiny
2
Q
cosx+y
A
cosxcosy±sinxsiny[change sign]
3
Q
cos2x
[in terms of tan]
A
1-tan2 /1+tan2
4
Q
cos2x
[in terms of cos&sin]
A
cos^2x- sin^2x
5
Q
sin2x
[in terms of tan]
A
2tanx/1+tan^2x
6
Q
tan2x
A
2tanx/1-tan^2x
7
Q
sin3x
A
3sinx-4sin^3x
8
Q
sinx+siny
A
2sin(x+y/2)cos(x-y/2)
9
Q
sinx-siny
A
2cos(x+y/2)sin(x-y/2)
10
Q
cosx+cosy
A
2cos(x+y/2)cos(x-y/2)
11
Q
cosx-cosy
A
-2sin(x+y/2)sin(x-y/2)
