• 2022-10-29
    二、单项选择题6.设f(x)为连续函数,()
    A: 2f(2)
    B: f(2)
    C: -f(2)
    D: 0
  • B

    内容

    • 0

      已知\( y = {f^2}(x) \),假设\( f(u) \)二阶可导,则 \( y'' \)为( ). A: \( 2{[f'(x)]^2} + 2f(x)f'(x) \) B: \( 2[f'(x)] + 2f(x)f''(x) \) C: \( 2{[f'(x)]^2} + 2f(x)f''(x) \) D: \( 2{[f'(x)]^2} + f(x)f''(x) \)

    • 1

      若函数$f(x)$具有二阶导数,且$y=f({{x}^{2}})$,则$y'' =$( )。 A: $f'' ({{x}^{2}})$ B: $2f'’ ({{x}^{2}})$ C: $2f’ ({{x}^{2}})+4{{x}^{2}}f’' ({{x}^{2}})$ D: $4{{x}^{2}}f’ ({{x}^{2}})+2f'' ({{x}^{2}})$

    • 2

      设函数f(x)=a|x|(a>0),且f(2)=4,则(  ) A: f(-1)>f(-2) B: f(1)>f(2) C: f(2)<f(-2) D: f(-3)>f(-2)

    • 3

      已知\( y = f({x^2}) \),假设\( f(u) \)二阶可导,则\( y'' \)为( ). A: \( 4{x^2}f''({x^2}){\rm{ + }}2f'({x^2}) \) B: \( {x^2}f''({x^2}){\rm{ + }}2f'({x^2}) \) C: \( 4{x^2}f''({x^2}){\rm{ + }}f'({x^2}) \) D: \( {x^2}f''({x^2}){\rm{ + }}f'({x^2}) \)

    • 4

      设f(x)是连续函数,且f(0)=1,则() A: 0 B: 1/2 C: 1 D: 2