∠A+∠B+∠C=180°∠A+∠C=2∠B ∠B =60°tan(A+C)=(tanA+tanC)/(1-tanAtanC)=tanBtanA+tanC=tanB(1-tanAtanC)=√3(1-2-√3)=-√3-3tanAtanC=2+√3由公式x^2+(p+q)x+pq=(x+p)(x+q)令a^2-(√3+3)a+(2+√3)=0(a-1)(a-2...