(1+根号3tana)(1+根号3tanb)=41+根号3(tana+tanb)+3tana*tanb=4根号3(tana+tanb)+3tanatanb=3tana+tanb+根号3tanatanb=根号3tana+tanb=根号3(1-tanatanb)=0tan(a+b)=(tana+tanb)/(1-tanatanb)=根号3锐角a.b,则0所以,a+b=60
