f(x)=4x³-5x²+x-2f'(x)=12x^2-10x+1f(1)-f(0)=f'(ζ)(1-0)12ξ^2-10ξ+1=0
ζ=(10+2根号13)/24 或 ζ=(10-2根号13)/24 而ζ∈[0,1]两个ζ均满足