已知函数f(x)=kx
3-3(k+1)x
2-2k
2+4,若f(x)的单调减区间为(0,4).
(1)求k的值;
(2)对任意的t∈[-1,1],关于x的方程2x
2+5x+a=f(t)总有实根,求实数a的取值范围.
考点分析:
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