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过抛物线y2=2px(p>0)的焦点作直线交抛物线于P(x1,y1),Q(x2,...
过抛物线y2=2px(p>0)的焦点作直线交抛物线于P(x1,y1),Q(x2,y2)两点,若x1+x2=3p,则|PQ|等于( )
A.4p
B.5p
C.6p
D.8p
考点分析:
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