013]解:(1)该抛物线过点,可设该抛物线的解析式为.

将,代入,

得解得

此抛物线的解析式为.························································ (3分)

(2)存在.··········································································································· (4分)

如图,设点的横坐标为,

则点的纵坐标为,

当时,

,.

又,

①当时,

,

即.

解得(舍去),.····························································· (6分)

②当时,,即.

解得,(均不合题意,舍去)

当时,.················································································· (7分)

类似地可求出当时,.································································· (8分)

当时,.

综上所述,符合条件的点为或或.······························ (9分)

(3)如图,设点的横坐标为,则点的纵坐标为.

过作轴的平行线交于.由题意可求得直线的解析式为. (10分)

点的坐标为..·· (11分)

.

当时,面积最大..···················································· (13分)

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