答：1+tanB/tanA=2c/(√3a)1+sinBcosA/(cosBsinA)= 2c/(√3a)(cosBsinA+sinBcosA)/(cosBsinA)= 2c/(√3a)sin(A+B)/(sinAcosB)=2c/(√3a)sinC/(sinAcosB)=2c/(√3a)=2sinC/(√3sinA) 根据正弦定理a/sinA=c/sinC所以：...