(来学网)若f"(x)存在,则函数y-ln[f(x)]的二阶导数为:
  • A.
    (来学网)
  • B.
    (来学网)
  • C.
    (来学网)
  • D.
    (来学网)ln"[f(x)]·f"(x)
正确答案:
A