已知函数f(x)满足f(x)=x^3+f'(2/3)x^2-x+c(c为常数).求f`(2/3)的值,求f(x)的单调区间求详细过程,谢谢

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已知函数f(x)满足f(x)=x^3+f''(2/3)x^2-x+c(c为常数).求f`(2/3)的值,求f(x)的单调区间求详细过程,谢谢已知函数f(x)满足f(x)=x^3+f''(2/3)x^2-x

已知函数f(x)满足f(x)=x^3+f'(2/3)x^2-x+c(c为常数).求f`(2/3)的值,求f(x)的单调区间求详细过程,谢谢
已知函数f(x)满足f(x)=x^3+f'(2/3)x^2-x+c(c为常数).求f`(2/3)的值,求f(x)的单调区间
求详细过程,谢谢

已知函数f(x)满足f(x)=x^3+f'(2/3)x^2-x+c(c为常数).求f`(2/3)的值,求f(x)的单调区间求详细过程,谢谢
首先要知道,f'(2/3)是一个常数.
f(x)=x^3+f'(2/3)x^2-x+c,对x求导,得:
f'(x)=3x^2+2f'(2/3)x-1
令x=2/3,则f'(2/3)=4/3+4/3*f'(2/3)-1
解方程得:f'(2/3)=-1
所以,f(x)=x^3-x^2-x+c
f'(x)=3x^2-2x-1
f'(x)>0,x∈(-∞,-1/3)∪(1,+∞),为增区间;
f'(x)

x^3如果是x的三次方的话f(2/3)=c-(2/3)

f'(x)=3x^2+2f'(2/3)x-1
f'(2/3)=3·4/9+2·2/3f'(2/3)-1
f'(2/3)=-1/3