tan(10+50)=(tan10+tan50)/(1-tan10tan50)=√3 tan10+tan50+√3tan10tan50=√3 tan(60-10)=(tan60-tan10)/(1+tan60tan10) 1+√3tan10=1+tan60tan10=(tan60-tan10)/tan50 sin50(1+√3tan10)=(tan60-tan10)cos50=(sin6...