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给出三个命题:①点P(b,a)在抛物线y=x2+1上;②点A(1,3)能在抛物线...
给出三个命题:①点P(b,a)在抛物线y=x2+1上;②点A(1,3)能在抛物线y=ax2+bx+1上;③点B(-2,1)能在抛物线y=ax2-bx+1上.若①为真命题,则( )
A.②③都是真命题
B.②③都是假命题
C.②是真命题,③是假命题
D.②是假命题,③是真命题
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