是log 以x为底么 如果是y=log x (lnx)=>log x (x^y) =log x (lnx)=>x^y=lnx求导得 yx^(y-1)*y'=1/x=>y'=x^(-1-y+1)*y=yx^y 将y=log x (lnx)带入y'=[log x (lnx)]*x^(log x (lnx))...