Trigonomic Identities Final Review Flashcards
0
Q
Sin(90’ - theta)
A
Cos theta
1
Q
What are the Pythagorean identities
A
Sin^2theta + cos^2theta = 1
1 + tan^2theta = sec^2theta
1 + cot^2theta = csc^2theta
2
Q
Sin2x
A
= 2sinxcosx
3
Q
1 + tan^2 theta
A
Sec^2 theta
4
Q
Sin(A+B)
A
sinAcosB + cosAsinB
5
Q
Sin x/2
A
= +_ square root of (1 - cos x / 2 )
6
Q
Tan (90’ - theta)
A
Cot theta
7
Q
Cos2x
A
= 2cos^2x - 1
= cos^2x - sin^2x
= 1 - sin^2x
8
Q
1 + cot^2 theta
A
= csc^2 theta
9
Q
Cos x / 2
A
= +_ square root of ( 1 + cosx / 2 )
10
Q
Sec (90’ - theta)
A
Csc theta
11
Q
Tan2x
A
= 2 tanx / 1 - tan^2 x
12
Q
Sin^2 + cos^2
A
= 1
13
Q
sin(A-B)
A
sinAcosB - cosAsinB
14
Q
Cos(A-B)
A
cosAcosB + sinAsinB
