正弦定理一1.5:32.根号3/33.2根号24.根号3/45由正弦定理可得:a=2RsinA,b=2RsinB ∵acosA=bcosB∴sinAcosA=sinBcosB∴A与B互余∴C=90°三角形ABC是直角三角形6.∵a/sinA=c/sinc∴2/(根号2/2)=根号6/sinC∴sinC=根号3/...