M - Pure 1 - 9) Trigonometric ratios Flashcards
1
Q
Formula for cosine rule to find a missing side
A
a = √[b² + c² - 2bc·cos(A)]
2
Q
Formula for cosine rule to find a missing angle
A
A = cos-1[(b² + c² - a²) / 2bc]
3
Q
Formula for sine rule to find a missing side
A
a = [b / sin(B)] × sin(A)]
4
Q
Formula for sine rule to find a missing angle
A
A = sin-1[(sin(B) / b) × a]
5
Q
Possible solutions of sine rule
A
- sin(θ)
- sin(180° - θ) → acute
6
Q
Formula for the area of a triangle
A
½ab·sin(C)
