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1、sin(C-A)=1,c-A=90°,C=90°+A,sinB=sin(180°-A-C)=sin(A+C)=sin(90°+2A)=sin(180°-90°-2A)=sin(90°-2A)=cos2A=1/3,sinA=√[(1-cos2A)/2]=√3/3.2、sinC=sin(90°+A)=cosA=√[1-(sinA)^2]=√6/3,根据正弦定理，c/sinC=b/sinB,c=[√6/(1/3)]√6/3=6,S△ABC=AB*AC*sinA/2=6*√6*√3/3/2=3√2. |
