# Sometimes expanding stuffs is very helpful!

Geometry Level 4

Given that $A, B,C$ are such real numbers for which all trigonometric functions are defined and $\dfrac{\tan(A-B)}{\tan(A)} + \dfrac{\sin^{2}(C)}{\sin^{2}(A)} = 1$, then the expression $\tan(A) \cdot \tan(B)$ is equal to:

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