Sine and Cosine rules Flashcards
1
Q
What type of triangle can the cosine rule be applied to?
A
Any triangle
2
Q
Use this to calculate an unknown side
A
a^2 = b^2 = c^2 - 2bcCosA
3
Q
Use this to calculate an unknown angle
A
cosA = b^2 = c^2 - a^2 over 2bc
4
Q
cosA = b^2 = c^2 - a^2 over 2bc
A
Use this to calculate an unknown angle
5
Q
a^2 = b^2 = c^2 - 2bcCosA
A
Use this to calculate an unknown side
6
Q
You can use to cosine rule to find:
A
- The length of a side if you know two sides and the included angle.
- An unknown angle if you know all three sides.
7
Q
What type of triangle can the sine rule be applied to?
A
Missing lengths in a scalene triangle.
8
Q
Formula for sine rule
A
a over sinA = b over sinB = c over sinC
9
Q
Area of a triangle
A
half x absinC
