Trigo-trigo
cos 77° · cos 43° – cos 47° · cos 13° = | |
sin 11° · cos 71° – sin 79° · sin 71° = |
Algebra-trigo
- (sin α + cos α)2 – 1 =
- 1 – (sin α + cos α)2 =
- (sin α – cos α)2 + sin 2α =
- (sin α + cos α)2 – sin 2α =
- (sin α + cos α)(sin α – cos α) =
- sin2α : (sin α + cos α)(cos α – sin α) =
- (tan 2α cos α – tan 2α sin α)(cos α + sin α) =
- tan
- tan
Trigo-algebra
- 2cos22α – cos 4α =
- 4sin2α cos2α + cos22α =
- tan α cos2α : sin 2α =
- sin(180° + 2α) : tan(180° – α) + 2sin2α =
- –0,5tan α(sin 2α – 2cos α) + sin2α – sin α =