AC⊥AB, DM⊥AC, SM⊥AB
stąd DM∥AB, SM∥AC, ΔSBM≈ΔDMC≈ΔABC
| |DM| | |CM| | |SM| | |BM| | ||||
= | oraz | = | |||||
| |AB| | |BC| | |AC| | |BC| |
| |DM| | ||
|CM|= | *|BC| | |
| |AB| |
| |SM| | ||
|BM|= | *|BC| | |
| |AC| |
| |DM| | |SM| | ||
*|BC|=|BC|− | *|BC| // : |BC| | ||
| |AB| | |AC| |
| |DM| | |SM| | ||
=1− | |||
| |AB| | |AC| |
| |DM| | |SM| | ||
+ | =1 | ||
| |AB| | |AC| |
| SM | BM | |||
SM || AC, więc | = | |||
| AC | BC |
| DM | CM | |||
DM || AB, więc | = | |||
| AB | CB |
| DM | SM | BM + CM | BC | ||||
+ | = | = | = 1 | ||||
| AB | AC | BC | BC |
elegancko i krótko