Jawabanmu

2014-05-30T17:23:38+07:00
2 sin alpha . cos alpha
Komentar sudah dihapus
2 tan α / (1 + tan² α)
= 2 tan α / sec²α (karena 1 + tan²α = sec²α)
= 2.(sin α/cos α) .cos²α
= 2.sin α.cos α
= sin 2α