高数。求极限。如何证明导数在0点的值？

φ'(0) = lim<x→0>[φ(x)-φ(0)]/(x-0) = lim<x→0>∫<0, x>tf(t)/x^3 (0/0)
= lim<x→0>xf(x)/(3x^2) = lim<x→0>f(x)/(3x) (0/0)
= lim<x→0>f'(x)/3 = f'(0)/3

温馨提示：答案为网友推荐，仅供参考

当前网址：https://verywind.cn/ee/vxr7vyy3rfvy2f2vy2j.html