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如图，抛物线E：y2＝4x的焦点为F，点M与F关于坐标原点O对称，过F的直线与抛物线交于A，B两点，使得AB⊥BM，又A点在x轴上的投影为C，则|AF|+|AC|﹣|BF|﹣|BC|＝ ．
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高三下学期数学《》真题及答案
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设斜率为2的直线l过抛物线y2＝axa≠0的焦点F.且和y轴交于点
，若△OAF(O.为坐标原点)的面积为4，则抛物线方程为( ) A.y
2
＝±4x
y
2
＝±8x
y
2
＝4x
y
2
＝8x
设斜率为2的直线l过抛物线y2＝axa≠0的焦点F.且和y轴交于点
若△OAF(O.为坐标原点)的面积为4，则抛物线方程为( ) A.y
2
＝±4x
y
2
＝±8x
y
2
＝4x
y
2
＝8x
从抛物线y2=4x上一点P引抛物线准线的垂线垂足为M且|PM|=5设抛物线的焦点为F则△MPF的面积
已知F.是抛物线y2=4x的焦点P是圆x2+y2-8x-8y+31=0上的动点则|FP|的最小值是
3
4
5
6
设斜率为2的直线l过抛物线y2＝axa≠0的焦点F.且和y轴交于点
，若△OAF(O为坐标原点)的面积为4，则抛物线方程为( ) A.y
2
＝±4x
y
2
＝±8x
y
2
＝4x
y
2
＝8x
已知A.是抛物线y2=4x上一点F.是抛物线的焦点直线FA交抛物线的准线于点B.点B.在x轴上方若|
过抛物线y2=4x的焦点F.的直线交该抛物线于A.B两点.若|AF|=3则|BF|=.
已知抛物线y2＝4x上一点M.与该抛物线的焦点F.的距离|MF|＝4则点M.的横坐标x0＝_____
已知抛物线y2=4x的焦点为F.过F.的直线与该抛物线相交于
(x1,y1)、
(x2,y2)两点,则
+
的最小值是( ) A.4 B.8
12
16
如图抛物线E.:y2=4x的焦点为F.准线l与x轴的交点为A.点C.在抛物线E.上以C.为圆心|CO
抛物线y2=4x的焦点为F.P.为抛物线上一点P.的横坐标为2则|PF|=
2
3
4
5
已知过抛物线y2=4x的焦点F.的直线交该抛物线于A.B.两点|AF|=2则|BF|=.
过抛物线y2=4x焦点的直线交抛物线于A.B.两点已知|AB|=8O.为坐标原点则△OAB的重心的横
如图抛物线关于x轴对称它的顶点在坐标原点点P12Ax1y1Bx2y2均在抛物线上．
设斜率为2的直线l过抛物线y2＝axa≠0的焦点F.且和y轴交于点
，若△OAF(O为坐标原点)的面积为4，则抛物线方程为( ) A.y
2
＝±4x
y
2
＝±8x
y
2
＝4x
y
2
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+
的最小值是( ) A.4 B.8 12 16
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