Geometry

Question 1

What is the cosine rule?

Answer 1

a^2 = b^2 + c^2 - 2bc cos A

Or

Cos A = (b^2 + c^2 - a^2) / 2bc

Question 2

Sine rule?

Answer 2

Sin A / a = Sin B / b = Sin C / c

Question 3

Area of a triangle formula?

Answer 3

1/2 ab Sin C

Question 4

How do you find arc length with radians?

Answer 4

r θ = arc length

Question 5

How do you find sector area with radians?

Answer 5

1/2 r^2 θ = sector area

Question 6

How do you find segment area with radians?

Answer 6

1/2 r^2 (θ - sin θ) = segment area