挑战习题
1/5单选题
难度:

1.如图,在平面直角坐标系中,已知抛物线y=−x2+x+1经过点A(0,1)、B(3,)两点,BC⊥x轴,垂足为C. 点P是线段AB上的一动点(不与A,B重合),过点P作x轴的垂线交抛物线于点M,设点P的横坐标为t. 连结PC,当t为()时,四边形PMBC是菱形?
A 1
B 2
C 3
D 4
提示1:
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正确答案:QQ==
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