Wyznacz sinusy katów ostrych trójkata prostokatnego wiedzac, ze stosunek promieni okregów
| 13 | ||
opisanego i wpisanego w ten trójkat jest równy | ||
| 4 |
| R | 13 | ||
= | |||
| r | 4 |
| 13 | ||
2R = c = | r | |
| 2 |
| a | 2 | a | ||||
sinα = | = | * ( | ) | |||
| c | 13 | r |
| a + b − c | ||
r = | ||
| 2 |
| 17 | 17 | |||
a + b = | r => b = | r − a | ||
| 2 | 2 |
| 17 | 169 | |||
a2 + ( | r − a)2 = | r2 | ||
| 2 | 4 |
| a2 | a | |||
2 | − 17 | + 30 = 0 | ||
| r2 | r |
| a | 13 | 13 | ||||
Podstawienie t = | −−> t ∊ (− | , | ) | |||
| r | 2 | 2 |
| 17 − 13 | ||
t1 = | = 1 | |
| 4 |
| 30 | ||
t2 = | ||
| 4 |
| 2 | ||
sinα = | ||
| 13 |
| π | ||
Chyba ze sinβ obliczyc z sin( | − α) ![]() | |
| 2 |
| 5 | ||
t1 = | ||
| 2 |
| 5 | ||
sinα = | , jednak co z sinusem drugiego kata? | |
| 13 |
| 2 | 12 | |||
sinα = | * 6 = | |||
| 13 | 13 |
| 2 | 5 | 5 | ||||
sinβ = | * | = | ||||
| 13 | 2 | 13 |