1. The question asks if I am knowledgeable about trigonometry, specifically the sine rule. 2. The sine rule states that in any triangle, the ratio of the length of a side to the sine of its opposite angle is constant. 3. Mathematically, for a triangle with sides $a$, $b$, $c$ and opposite angles $A$, $B$, $C$, the sine rule is: $$\frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C}$$ 4. I can help you solve problems involving the sine rule step-by-step, explain concepts, or work through examples.