f(x)在[0,1]上可导,f(0)=0,f(1)=1,且f(x)不恒等于x.证明存在a∈(0,1),使f'(a)>1
1,则f'(a)≤1∫[0,1] [f'(x)-1]dx ≤ 0因为f'(x)不恒等于1所以∫[0,1] [f'(x)-1]dx"}}}'>