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设a,b是方程x2+x-2009=0的两个实数根,则a2+2a+b的值为( ) ...
设a,b是方程x2+x-2009=0的两个实数根,则a2+2a+b的值为( )
A.2006
B.2007
C.2008
D.2009
考点分析:
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C.3y
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B.有两个负根
C.有一个正根一个负根
D.没有实数根
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已知
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