Trig Identities Flashcards
1
Q
Cos(A+B)
A
cosAcosB-sinAsinB
2
Q
Cos(A-B)
A
cosAcosB+sinAsinB
3
Q
Sin(A+B)
A
sinAcosB+sinBcosA
4
Q
Sin(A-B)
A
sinAcosB-cosAsinB
5
Q
cos(2A)
A
cos^2A-sin^2A
6
Q
sin(2A)
A
2sinAcosA
7
Q
tanO
A
QI or II is y/x
Q III or IV is y/x +pi
8
Q
cos^2A
A
1/2+1/2cos2A
9
Q
sin^2A
A
1/2+1/2cos2A
10
Q
Trig Identities
A
cos^2x+sin^2x=1
cot^2x + 1 = csc^2x
tan^2+1 = sec^2x
