/c=sinB/sinC=2/√3,
B-C=π/6,B=C+π/6
sin(C+π/6)/sinC=2/√3
(sinC√3/2+cosC/2)/sinC=2/√3
√3/2+cotanC/2=2/√3
cotanC=√3/3=>tanC=√3=>C=π/3,=>B=π/2=>A=π/6
/c=sinB/sinC=2/√3,
B-C=π/6,B=C+π/6
sin(C+π/6)/sinC=2/√3
(sinC√3/2+cosC/2)/sinC=2/√3
√3/2+cotanC/2=2/√3
cotanC=√3/3=>tanC=√3=>C=π/3,=>B=π/2=>A=π/6