Question

如图,已知△ABC中,∠B=45°,∠C=30°,BC=4+2√3,求AB、AC的长

Answer 1

∠A=180°-∠B-∠C=105°∴ sinA=sin105°=(√6+√2)/4利用正弦定理：AB/sinC=AC/sinB=BC/sinA∴ AB=BCsinC/sinA=(4+2√3)*(1/2)/[(√6+√2)/4]=(8+4√3)/(√6+√2)=(6+4√3+2)/(√6+√2)=(√6+√2)²/(√6+√2)...