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不等式(a-2)x2+2(a-2)x-4<0对x∈R恒成立,则实数a的取值范围是...
不等式(a-2)x2+2(a-2)x-4<0对x∈R恒成立,则实数a的取值范围是( )
A.(-∞,2)
B.[-2,2]
C.(-2,2]
D.(-∞,-2)
考点分析:
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