3对数函数y= log, x(a>0,a≠1)y=Inx y J=loga x (1,9) > 2468101214 0.5 y=logIx -1,53.对数函数 y = log x (a  0,a  1) a y = ln x y = loga x y x a 1 = log(a  1) (1,0)