Rownanie trygonom
5-latek: Rozwiazac rownanie
(sin4x−2cos4x)
2+(cos4x−2sin4x)
2=3
sin
24x−4sin4xcos4x+4cos
24x+cos
24x−4cos4xsin4x+4sin
24x= 3
sin
24x+cos
24x+4(cos
24x+sin
24x)−8sin4xcos4x=3
1+4−3−8sin4xcos4x=0
2−8sin4xcos4x=0
8sin4xcos4x=2
Jak dalej pociagnac to?
5-latek: Witam
sin2x= 2sinxcosx
sin4x= 2sin2xcos2x
sin8x= 2sin4xcos4x
| 1 | |
wiec sin4xcos4x= |
| sin8x |
| 2 | |
Wiesz nie wiedzialem dokladnie co z ta 2 na poczatku
myslaem ze sin4x= 2*2sin2xcos2x= 4sin2xcos2x
wiec dokoncze to rownanie
| π | | 3 | | 1 | |
8x= |
| +2kπ to x= |
| π+ |
| kπ |
| 6 | | 4 | | 4 | |
| π | | 5 | | 1 | |
8x= π− |
| +2kπ to x= |
| π+ |
| kπ |
| 6 | | 48 | | 4 | |