题目

已知实数x满足(x2﹣x)2﹣4(x2﹣x)﹣12=0,则代数式x2﹣x+1的值是( )A. 7 B. ﹣1 C. 7或﹣1 D. ﹣5或3 答案:【答案】A【解析】将x2-x看作一个整体,然后利用因式分解法解方程求出x2-x的值,再整体代入进行求解即可.∵(x2﹣x)2﹣4(x2﹣x)﹣12=0,∴(x2﹣x+2)(x2﹣x﹣6)=0,∴x2﹣x+2=0或x2﹣x﹣6=0,∴x2﹣x=﹣2或x2﹣x=6;当x2﹣x=﹣2时,x2﹣x+2=0,∵b2﹣4ac=1﹣4×1×2=﹣7<0,∴此方程无实数解;当x2﹣x=6时,xWe   read 100 poems by the end of this term. A.will          B.will have C.have          D./  
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