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抛物线顶点在原点,焦点在x轴上,其上一点P(1,m)到焦点的距离为3,则抛物线方...
抛物线顶点在原点,焦点在x轴上,其上一点P(1,m)到焦点的距离为3,则抛物线方程为( )
A.x2=8y
B.y=8x2
C.y2=4
D.y2=8
考点分析:
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