sin75? = sin(30? + 45?) = sin30?cos45? + cos30?sin45?
sin30? = 1/2?cos45? = ?2/2?cos30? = ?3/2?sin45? = ?2/2?sin75? = (1/2) * (?2/2) + (?3/2) * (?2/2) = (?2/4) + (?6/4) = (?2 + ?6) / 4
sin75 (?6 + ?2) / 4?sin75? = sin(30? + 45?) = sin30?cos45? + cos30?sin45?
sin30? = 1/2?cos45? = ?2/2?cos30? = ?3/2?sin45? = ?2/2?sin75? = (1/2) * (?2/2) + (?3/2) * (?2/2) = (?2/4) + (?6/4) = (?2 + ?6) / 4
sin75 (?6 + ?2) / 4?