Trig Identities Flashcards
1
Q
Reciprocal Identity:
sinx
A
1/cscx
2
Q
Reciprocal Identity:
cosx
A
1/secx
3
Q
Reciprocal Identity:
tanx
A
1/cotx
4
Q
Reciprocal Identity:
cotx
A
1/tanx
5
Q
Reciprocal Identity:
cscx
A
1/sinx
6
Q
Reciprocal Identity:
secx
A
1/cosx
7
Q
Pythagorean Identity:
sin^2(x) + cos^2(x)
A
1
8
Q
Pythagorean Identity:
1 + tan^2(x)
A
sec^2(x)
9
Q
Pythagorean Identity:
1 + cot^2(x)
A
csc^2(x)
10
Q
Double Angle Formulas:
sin(2x)
A
2sinxcosx
11
Q
Double Angle Formulas:
cos(2x)
A
= cos^2(x) - sin^2(x)
= 2cos^2(x) - 1
= 1-2sin^2(x)
12
Q
Double Angle Formulas:
tan(2x)
A
(2tanx) / (1 - tan^2(x))
13
Q
Power Reducing/ Half Angle:
sin^2(x)
A
(1 - cos(2x)) / 2
14
Q
Power Reducing/ Half Angle:
cos^2(x)
A
(1 + cos(2x)) / 2
15
Q
Power Reducing/ Half Angle:
tan^2(x)
A
(1 - cos(2x)) / (1 + cos(2x))
