f(x)在[0,+∞)上可导,且0≤f(x)≤x/(1+x²) 证明:存在ξ,使f'(ξ)=(1-ξ²)/(1+ξ²)²

问题描述:

f(x)在[0,+∞)上可导,且0≤f(x)≤x/(1+x²) 证明:存在ξ,使f'(ξ)=(1-ξ²)/(1+ξ²)²