Ewentualnie możesz dorysować sobie prostą
\(\displaystyle{ EH \parallel AB}\) oraz
\(\displaystyle{ BF \perp AB}\) zawierającą się w stycznej do okręgu opisanego na "mniejszym" trójkącie
\(\displaystyle{ ABC}\). Potrafisz powiedzieć dlaczego
\(\displaystyle{ \measuredangle CBF = \measuredangle BAC}\) ? Potem już łatwo.
\(\displaystyle{ \pagestyle{empty}
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