# Definitely tougher than previous one

Geometry Level 5

$\sum_{n = 1}^{K} \frac {\sin (n \theta)} { 2^n}\,=\,\dfrac{a^{K+1}\cdot \sin(\theta)\,+\,\sin(K \theta)\,-\,a \cdot \sin((K+1)\theta)}{2^{K}(b-c \cdot \cos(\theta))}$

The equation above holds true for constants $$a,b,c$$ and $$\theta$$. Find the value of $$a+b+c$$.

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