根据正弦定理:c/sinC=a/sinA
a√2/sin120°=a/sinA
√2/cos30°=1/sinA
sinA=cos30°/√2=√6/4=0.6123724356957945
∠A=37.76°
∠B=180°-120°-37.76°=22.24°
sin22.24°=0.378487074294548≈0.3785
a√2/sin120°=c/sinC
a√2/cos30°=c/sinC
2a√6/3=c/sinC
c=2a√6/3sinC=2a√6/3*0.3785=a0.6180879117622886≈a0.618
a/b=a/a0.618=1.618122977346278≈1.618