Počet úhlopříček v n-úhelníku
Kolik úhlopříček bude mít daný \( n \)−úhelník?
\( \large n = 13 \)
\( \large x = \Large \frac{n\cdot \left( n-3 \right) }{2}\large = \Large \frac{13\cdot \left( 13-4 \right) }{2}\large = \Large \frac{13\cdot 9}{2}\large = \Large \frac{117}{2}\large = 58.5 \)
\( \large x = \Large \frac{n\cdot \left( n-3 \right) }{2}\large = \Large \frac{13\cdot \left( 13-5 \right) }{2}\large = \Large \frac{13\cdot 8}{2}\large = \Large \frac{104}{2}\large = 52 \)
\( \large x = \Large \frac{n\cdot \left( n-3 \right) }{2}\large = \Large \frac{13\cdot \left( 13-3 \right) }{2}\large = \Large \frac{13\cdot 10}{2}\large = \Large \frac{130}{2}\large = 65 \)
\( \large x = \Large \frac{n\cdot \left( n-3 \right) }{2}\large = \Large \frac{13\cdot \left( 13-2 \right) }{2}\large = \Large \frac{13\cdot 11}{2}\large = \Large \frac{143}{2}\large = 71.5 \)