TrigonometrySuperchallenge ShareTrigonometry · Superchallenge problemEvaluate exactly:∑k=189sin3k∘sin3k∘+cos3k∘=sin31∘sin31∘+cos31∘+sin32∘sin32∘+cos32∘+⋯+sin389∘sin389∘+cos389∘.\sum_{k=1}^{89}\frac{\sin^3 k^\circ}{\sin^3 k^\circ + \cos^3 k^\circ} = \frac{\sin^3 1^\circ}{\sin^3 1^\circ + \cos^3 1^\circ} + \frac{\sin^3 2^\circ}{\sin^3 2^\circ + \cos^3 2^\circ} + \cdots + \frac{\sin^3 89^\circ}{\sin^3 89^\circ + \cos^3 89^\circ}.k=1∑89sin3k∘+cos3k∘sin3k∘=sin31∘+cos31∘sin31∘+sin32∘+cos32∘sin32∘+⋯+sin389∘+cos389∘sin389∘.Check Show answer Walk through it step by step Practice more like this