解答:∵向量FA与x轴正向夹角为60°,∴直线FA的斜率k=tan60°=√3,且A在F的右侧。∴直线FA的方程是:y=√3(x-p/2)将直线方程代入y²=2px∴3(x-p/2)²=2px∴3x²-3px+3p²/4 = 2px∴ 12x²-20px+3p²=0∴ (6x-p)(2x-3p)=0∴ x=p/6或x=3p/2∵ A在F右侧∴ xA=3p/2, ∴ yA=√3p∴ |OA|=√(9p²/4+3p²)=√(21p)/2