3、单选-|||-设f-|||-A (x)Delta xgt (int )_(x)^x+Delta xf(t)dtgt 0-|||-B (int )_(x)^x+Delta xf(t)dtlt f(x)Delta xlt 0-|||-C (x)Delta xlt (int )_(x)^x+Delta xf(t)dtlt 0-|||-D (int )_(x)^x+Delta xf(t)dtgt f(x)Delta xgt 0

(B) (int )_(x)^x+Delta xf(t)dtlt f(x)Delta xlt 0.-|||-(C) (x)Delta xgt (int )_(x

(B) (int )_(x)^x+Delta xf(t)dtlt f(x)Delta xlt 0.-|||-(C) (x)Delta xgt (int )_(x

设(x)=dfrac ({x)^2}(x-a)(int )_(a)^xf(t)dt, 其中f(x)设(x)=dfrac ({x)^2}(x-a)(int )_(

设f(x)在[a，b]上连续，F(x)=(int )_(a)^xf(t)dt，则(,)A. $F\left(x\right)$是$f\left(x\right)

设f(x)可微，且满足=(int )_(0)^xf(t)dt+(int )_(0)^xtf(t-x)dt，则f(x)=．设f(x)可微，且满足，则f(x)=．

设f(x)连续,则 dfrac (d)(dx)(int )_(0)^xtf((x)^2-(t)^2)dt= ()-|||-A、xf(x^2)-|||-B、 -x

设f(x)在 [ 0,+infty ) 上非负连续,且 (x)(int )_(0)^xf(x-t)dt=2(x)^3, 则 f(x)=

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

(4)设 (x)=(e)^sqrt (x) 则 lim _(Delta xarrow 0)dfrac (f(1+Delta x)-f(1))(Delta x)=

1.已知f`(x0)存在,则由导数定义知, lim _(Delta xarrow 0)dfrac (f({x)_(0)-Delta x)-f((x)_(0))}