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函数f(x)=12x+3ax2-2x3在区间[-1,1]上递增,则实数a的取值范...
函数f(x)=12x+3ax2-2x3在区间[-1,1]上递增,则实数a的取值范围是( )
A.[-1,1]
B.(-1,1)
C.[-2,2]
D.(-2,2)
考点分析:
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无最大值
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