Question

ANSWER ALL THE
4. IfA
IA-G18 C :)
and (A+B) - A²+B, find a and b.​

Answer 1

Answer:

Step-by-step explanation:

Given sin(θ+α)=a⟹cos(θ+α)=1−a2

​

sin(θ+β)=b⟹cos(θ+β)=1−b2

​

cos(α−β)=cos(θ+α−(θ+β))=cos(θ+α)cos(θ+β)+sin(θ+α)sin(θ+β)=(1−a2)(1−b2)

​+ab

cos2(α−β)=(1−a2)(1−b2)+a2b2+2ab(1−a2)(1−b2)

​=1−a2−b2+2a2b2+2ab(1−a2)(1−b2)

​

So

2cos2(α−β)−1−4abcos(α−β)

=2−2a2−2b2+4a2b2+4ab(1−a2)(1−b2)

​−1−4a2b2−4ab(1−a2)(1−b2)

​

=1−2a2−2b2