Y2, C5 - Radians Flashcards
1
Q
How often does sinx repeat
A
Every 2pi
sinx = sin(pi - x)
2
Q
How often does cosx repeat
A
Every 2pi
cosx = cos(2pi - x)
3
Q
How often does tanx repeat
A
Every pi
tanx = tan(pi + x)
4
Q
How to convert from radians to degrees
A
Divide by pi
Then multiply by 180
5
Q
Formula for arc length in radians and degrees
A
l = rθ
l = (θ / 360) x 2pi r
6
Q
Formula for sector area in radians and degrees
A
A = 1/2 * r^2 * θ
A = (θ / 360) * pi * r^2
7
Q
Formula for segment area in radians
A
A = 1/2 * r^2 * (θ - sinθ)
8
Q
What is the only unit that small angle approximations work for
A
Radians
9
Q
What is the small angle approximation for sinx
A
sinx = x
(radians)
10
Q
What is the small angle approximation for cosx
A
cosx = 1 - (x^2 / 2)
(radians)
11
Q
What is the small angle approximation for tanx
A
tanx = x
(radians)
