第1797题：常用导数公式
以下导数公式，正确的有( ).
A. (1x)′=1lnx(\dfrac{1}{x})' = \dfrac{1}{\ln x}(x1)′=lnx1
B. (logax)′=1lna (\log_a x)'= \dfrac{1}{\ln a}(logax)′=lna1
C. (arcsinx)′=11−x2(\arcsin x)'= \dfrac{1}{\sqrt{1-x^2}}(arcsinx)′=√1−x21
D. (arccosx)′=−11−x2(\arccos x)'= -\dfrac{1}{\sqrt{1-x^2}}(arccosx)′=−√1−x21
E. (arctanx)′=−11−x2(\arctan x)'= -\dfrac{1}{1-x^2}(arctanx)′=−1−x21
