来自崔志成的问题
设函数f(x)=n2x2(1-x)n(n为正整数),则f(x)在[0,1]上的最大值为4(nn+2)n+24(nn+2)n+2.
设函数f(x)=n2x2(1-x)n(n为正整数),则f(x)在[0,1]上的最大值为4(nn+2)n+2
4(nn+2)n+2
.
1回答
2020-12-28 04:55
设函数f(x)=n2x2(1-x)n(n为正整数),则f(x)在[0,1]上的最大值为4(nn+2)n+24(nn+2)n+2.
设函数f(x)=n2x2(1-x)n(n为正整数),则f(x)在[0,1]上的最大值为4(nn+2)n+2
4(nn+2)n+2
.
f′(x)=2n2x(1-x)n-n×n2x2(1-x)n-1=n2x(1-x)n-1(2-2x-nx)=-n2x(1-x)n-1[(n+2)x-2]=0得x=0,或x=1,或x=2n+2f(x)在[0,1]上是x的变化情况如下:∴f(x)在[0,1]上的最大值为4(nn+2)n+2故答案为:4(...