是求微分的一种方法,办法是:先取对数,再求导数,以使算法简便比如,设y=((x+2)^2/((x-5)(x+3))^(1/3),求y'两边取对数,得:lny=(1/3)(2ln(x+2)-ln(x-5)-ln(x+3))两边求导,得:(1/y)y'=(1/3)(2/(x+2)-1/(x-5)-1/(x+3))y'=(...