• 2021-04-14
    【单选题】若 f ( x ) = ( x − 1 ) x 2 − 1 2 , g ( x ) = x − 1 x + 1 ,则?
    A. f ( x ) = g ( x ) "> f ( x ) = g ( x ) B. lim x → 1 f ( x ) = g ( x ) "> lim x → 1 f ( x ) = g ( x ) C. lim x → 1 f ( x ) = lim x → 1 g ( x ) "> lim x → 1 f ( x ) = lim x → 1 g ( x ) D. 以上等式均不成立
  • lim x → 1 f ( x ) = lim x → 1 g ( x ) "> lim x → 1 f ( x ) = lim x → 1 g ( x )
    本题目来自[网课答案]本页地址:https://www.wkda.cn/ask/xpotmpjzeopamxo.html

    内容

    • 0

      若x-x0,limf(x)=A,则必有() A: lim[f(x)]=[A] B: limsgnf(x)=sgnA C: lim|f(x)|=|A| D: lim1/f(x)=1/A

    • 1

      设f(x),g(x)是恒不为零的可导函数,且f’(x)g(x)-f(x)g’(x)>0,则当0<x<1时()。 A: f(x)g(x)>f(1)g(1) B: f(x)g(x)>f(0)g(0) C: f(x)g(1)<f(1)g(x) D: f(x)g(0)<f(0)g(x)

    • 2

      设f(x)=lnxx,则lim△x→0f(1+△x)-f(1)△x=(  )

    • 3

      下列函数相等的是( )。 A: \( f(x) = \ln {x^2},g(x) = 2\ln x \) B: \( f(x) = x,g(x) = \sqrt { { x^2}} \) C: \( f(x) = \sqrt { { x^2}} ,g(x) = \left| x \right| \) D: \( f(x) = { { {x^2} - 1} \over {x - 1}},g(x) = x + 1 \)

    • 4

      若函数f(x)=x3+1x,则lim△x→0f(△x-1)+f(1)2△x=______.