(B)若 lim _(xarrow 0)dfrac (f(x)+f(-x))(x) 存在,则 (0)=0.-|||-(C)若 lim _(xarrow 0)dfrac (f(x))(x) 存在,则f`(0)存在. (D)若 lim _(xarrow 0)dfrac (f(x)-f(-x))(x) 存在,则f`(0)存在.

已知f(x)满足 lim _(xarrow 1)dfrac (f(x))(ln x)=1, 则 () .-|||-(A) f(1)=0 (B) lim _(xa

已知 lim _(xarrow 0)([ 1+x+dfrac {f(x))(x)] }^dfrac (1{x)}=(e)^3, 则 lim _(xarrow 0

设 lim _(xarrow 0)((1+x+dfrac {f(x))(x))}^dfrac (1{x)}=(e)^3 ,则 lim _(xarrow 0)((

设lim _(xarrow 0)dfrac (ln (1+x+dfrac {f(x))(x))}(x)=3，则lim _(xarrow 0)dfrac (ln

1.若f(x)在 x=0 处可导,且 (0)=0, 则 lim _(xarrow 0)dfrac (f(x))(x)= __

若(0)=0, lim _(xarrow 0)dfrac (f(2x))(x)=4, 则 (0)=若

若函数f(x)在 x=0 处连续,且 lim _(xarrow 0)dfrac (f(x))(x) 存在,证明 f(x)在 x=0 处可导.

19.若 ((x)_(0))=-2 ,则 lim _(Delta xarrow 0)dfrac (f({x)_(0)+Delta x)-f((x)_(0))}(

[题目]设函数f (x)在 x=0 处连续,下列命题错误-|||-的是 ()-|||-A.若 lim _(xarrow 0)dfrac (f(x))(x) 存在

[题目]-|||-设 ((x)_(0))=3 则 lim _(xarrow 0)dfrac (f({x)_(0)+x)-f((x)_(0)-3x)}(x)= _