Chapter 7 Key Equations Flashcards
1
Q
cos(-x) =
A
cosx
2
Q
cot(-x) =
A
-cotx
3
Q
sin(-x)=
A
-sinx
4
Q
tan(-x)=
A
-tan(x)
5
Q
cos^2x + sin^2x =
A
1
6
Q
1 + tan^2x =
A
sec^2x
7
Q
cot^2x + 1 =
A
csc^2x
8
Q
cot^2x =
A
csc^2x - 1
9
Q
tan^2x - sec^2x =
A
-1
10
Q
tanx =
A
sinx/cosx
11
Q
cotx =
A
cosx/sinx
12
Q
sin(a+B) =
A
sinacosB + cosasinB
13
Q
cos(a+B) =
A
cosacosB - sinasinB
14
Q
tan(a+B) =
A
tan(a) + tan(B) / 1 - tan(a)tan(B)
15
Q
sin(t)
A
cos(π/2 - t)
16
Q
cos(t)
A
sin(π/2 - t)
17
Q
sin2x =
A
2sinxcosx
18
Q
cos2x =
A
cos^2x-sin^2x
19
Q
2cos^2x-1
A
cos2x
20
Q
1 - 2sin^2x
A
= cos2x
21
Q
sin^2x =
A
1 - cos2x / 2
22
Q
cos^2x =
A
1 + cos2x / 2
23
Q
sin x/2 =
A
± √1-cosx / 2
24
Q
cos x/2 =
A
± √1+cosx / 2
25
sinxsiny =
1/2[cos(x-y)-cos(x+y)]
26
cosxcosy =
1/2[cos(x-y)+cos(x+y)]
27
sinxcosy =
1/2[sin(x+y)+sin(x-y)]
28
cosxsiny =
1/2[sin(x+y)-sin(x-y)]
29
sinx + siny =
2sin(x+y/2)cos(x-y/2)
30
sinx - siny =
2cos(x+y/2)sin(x-y/2)
31
cosx + cosy =
2cos(x+y/2)cos(x-y/2)
32
cosx - cosy =
-2sin(x+y/2)sin(x-y/2)
