Card 1 of 20
When expanding sin(θ±ϕ)\sin(\theta\pm\phi)sin(θ±ϕ), which sign is used between the products?
A
The sine addition identity is sin(θ+ϕ)=\sin(\theta+\phi)=sin(θ+ϕ)= sinθcosϕ+cosθsinϕ\boxed{\sin\theta\cos\phi+\cos\theta\sin\phi}sinθcosϕ+cosθsinϕ.
B
The cosine difference identity is cos(θ−ϕ)=\cos(\theta-\phi)=cos(θ−ϕ)= cosθcosϕ+sinθsinϕ\boxed{\cos\theta\cos\phi+\sin\theta\sin\phi}cosθcosϕ+sinθsinϕ.
C
Use the same sign as between the angles.
D
2−32-\sqrt32−3
Card 1 of 20
1.7.18 Compound angle formulae (A-level only) Flashcards
20 flashcards on OCR (MEI) A Level Maths 1.7.18 Compound angle formulae (A-level only): the key formulae, methods and definitions you need to recall for Component 01, Component 02 and Component 03.