​$$\frac{\cos 41^\circ}{\sin 49^\circ} + \frac{\sin 51^\circ}{\cos 39^\circ}$$​​

Complementary Angles: $$\sin(90^\circ - \theta) = \cos(\theta) \quad \text{and} \quad \cos(90^\circ - \theta) = \sin(\theta)$$  

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