Dan je trokut
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takav da je
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. Neka je
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polovište stranice
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,
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. Dokažite da je
%V0
Dan je trokut $ABC$ takav da je $|AC| \neq |BC|$. Neka je $M$ polovište stranice $\overline{AB}$, $\alpha = \angle BAC, \beta = \angle ABC, \varphi = \angle ACM, \psi = \angle BCM$. Dokažite da je
$$\frac{\sin \alpha \sin \beta}{\sin(\alpha - \beta)} = \frac{\sin \varphi \sin \psi}{\sin (\varphi - \psi)}.$$