根据积化和差公式：cosαsinβ ＝ 0.5 * [sin(α + β) - sin(α - β)]
cos6xsin3x = 0.5 * [sin9x - sin3x]
∫sin3xcos6x ＝ 0.5∫[sin9x - sin3x] = 0.5 * [- cos9x / 9 + cos3x / 3] + C
根据积化和差公式：cosαsinβ ＝ 0.5 * [sin(α + β) - sin(α - β)]
cos6xsin3x = 0.5 * [sin9x - sin3x]
∫sin3xcos6x ＝ 0.5∫[sin9x - sin3x] = 0.5 * [- cos9x / 9 + cos3x / 3] + C