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若f(x)=-x2+2ax与g(x)=(a+1)1-x在区间[1,2]上都是减函...
若f(x)=-x2+2ax与g(x)=(a+1)1-x在区间[1,2]上都是减函数,则a的取值范围是( )
A.(-1,0)
B.(-1,0)∪(0,1]
C.(0,1]
D.(0,1)
考点分析:
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