√3b=2asinB正弦定理√3sinB=2sinAsinBsinA=√3/2∵A是锐角∴A=π/3
解：（1）在△ABC中，a=2RsinA,b=2RsinB∵√3b=2asinB ∴√3×2RsinB=2×2RsinAsinB∴√3=2sinA ∴sinA=√3/2∴A=60°
2sinA*2R*sinB=根号3*sinB*2R2sinA=根号3sinA=根号3/2A=60°
