Three sided of a triangle have equations `L_1-=y-m_i x=o; i=1,2a n d3.` Then `L_1L_2+lambdaL_2L_3+muL_3L_1=0` where `lambda!=0,mu!=0,` is the equation of the circumcircle of the triangle if `1+lambda+mu=m_1m_2+lambdam_2m_3+lambdam_3m_1` `m_1(1+mu)+m_2(1+lambda)+m_3(mu+lambda)=0` `1/(m_3)+1/(m_1)+1/(m_1)=1+lambda+mu` none of these