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不等式x2+2x+a≥-y2-2y对任意实数x、y都成立,则实数a的取值范围是(...
不等式x2+2x+a≥-y2-2y对任意实数x、y都成立,则实数a的取值范围是( )
A.a≥0
B.a≥1
C.a≥2
D.a≥3
考点分析:
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