trigonometry Flashcards
1
Q
30° in radians
A
π/6
2
Q
45° in radians
A
π/4
3
Q
60° in radians
A
π/3
4
Q
90° in radians
A
π/2
5
Q
180° in radians
A
π
6
Q
270° in radians
A
3π/2
7
Q
360° in radians
A
2π
8
Q
arc length formula
[radians]
A
rθ
9
Q
area of a sector formula
[radians]
A
½ r²θ
10
Q
area of a segment formula
[radians]
A
½ r² (θ - sinθ)
11
Q
sin(π ⁄6)
A
½
12
Q
sin(π ⁄3)
A
√3 ⁄2
13
Q
sin(π ⁄4)
A
√2⁄ 2
14
Q
cos(π ⁄6)
A
√3 ⁄2
15
Q
cos(π ⁄3)
A
½
16
Q
cos(π ⁄4)
A
√2 ⁄2
17
Q
tan (π ⁄6)
A
√3 ⁄3
18
Q
tan (π ⁄3)
A
√3
19
Q
tan (π ⁄4)
A
1
20
Q
what is sin θ small angle approximation
A
≈θ
21
Q
what is cosθ small angle approximation
A
≈ 1 - θ² ⁄2
22
Q
what is tanθ small angle approximation
A
≈ θ
23
Q
how to convert from degrees to radians
A
converting degrees to radians you multiply by π/ 180
24
Q
how to convert from radians to degrees
A
converting radians to degrees you multiply by
180/ π
25
what is the identity involving sin²x and cos²x
sin²x + cos²x = 1
26
in what way is cot x related to sinx and cos x
cot x is the inverse of tan x and the inverse of tan x is equal to cos x/ sin x
27
what is the identity involving cot²x and cosec²x
1 + cot²x =cosec²x
28
what is the inverse of sin x
1/ sin x = cosec x
29
what is the inverse of cos x
1/ cos x = sec x
30
what is the inverse of tan x
1/ tan x = cot x
31
area of a sector [degrees]
(θ/360º) × πr²
32
arc length [degrees]
2πr x (θ/360º)
33
area of a segment [degrees]
πr² x (θ/360º)
