A.It means you are in another country. B.It memos you are in a bad mood. C.It means you have made a mistake. D.It means you have some trouble to handle.
【简答题】(1)定理:若函数f(x)的图象在区间[a,b]上连续,且在(a,b)内可导,则至少存在一点ξ∈(a,b),使得f(b)-f(a)=f′(ξ)(b-a)成立.应用上述定理证明: ①1- x y <lny-lnx< y x -1(0<x<y) ; ② n k-2 1 k <lnn< n-1 k-1 1 k (n>1) . (2)设f(x)=x n (n∈N * ).若对任意的实数x,y,f(x)-f...