P1 Radians and Triangles

Question 1

Formula for Arc Length in radians:

Answer 1

r x θ

Question 2

Formula for area of a sector in radians:

Answer 2

1/2 x r^2 x θ

Question 3

Formula for a segment in radians:

Answer 3

1/2 x r^2(θ - sin(θ))

Question 4

What is a segment:

Answer 4

An area of a circle separated by a chord, there is a minor and major segment, major is the bigger segment.

Question 5

How to convert between degrees and radians?

Answer 5

Angle in Radians = Angle in Degrees × π/180°

Question 6

How to calculate the area of a triangle

Answer 6

1/2 absinC
1/2 base x height

Question 7

2 sin rules

Answer 7

Area = 1/2 * a * b * sin(C)
a / sin(A) = b / sin(B) = c / sin(C)

Question 8

2 cos rules

Answer 8

c² = a² + b² - 2ab * cos(C)
cos(C) = (a² + b² - c²) / (2ab)

Question 9

How to calculate hypotenuse

Answer 9

c² = a² + b²