• 2022-06-17
    函数\(y = 1{\rm{ + }}{1 \over x}\)的导数为( ).
    A: \({\rm{ - }}{1 \over { { x^2}}}\)
    B: \({1 \over { { x^2}}}\)
    C: \(\ln \left| x \right|\)
    D: \( - \ln \left| x \right|\)
  • A

    内容

    • 0

      \(\lim \limits_{x \to 1} { { \sin \left( { { x^2} - 1} \right)} \over {x - 1}}{\rm{ = }}\)______ 。

    • 1

      函数\(y = \ln \ln x\)的导数为( ). A: \({1 \over {x\ln x}}\) B: \( - {1 \over {x\ln x}}\) C: \({1 \over {\ln x}}\) D: \( - {1 \over {\ln x}}\)

    • 2

      函数\(z = {\left( {xy} \right)^x}\)的全微分为 A: \(dz = \left( { { {\left( {xy} \right)}^x} + \ln xy} \right)dx + x{\left( {xy} \right)^x}dy\) B: \(dz = \left( { { {\left( {xy} \right)}^x} + \ln xy} \right)dx + { { x { { \left( {xy} \right)}^x}} \over y}dy\) C: \(dz = {\left( {xy} \right)^x}\ln xydx + { { x { { \left( {xy} \right)}^x}} \over y}dy\) D: \(dz = {\left( {xy} \right)^x}\left( {1 + \ln xy} \right)dx + { { x { { \left( {xy} \right)}^x}} \over y}dy\)

    • 3

      \( {1 \over {1 + x}} \)的麦克劳林公式为( )。 A: \( {1 \over {1 + x}} = 1 + x + { { {x^2}} \over 2} + \cdots + { { {x^n}} \over {n!}} + o\left( { { x^n}} \right) \) B: \( {1 \over {1 + x}} = 1 + x + {x^2} + \cdots + {x^n} + o\left( { { x^n}} \right) \) C: \( {1 \over {1 + x}} = 1 - x + {x^2} - \cdots + {( - 1)^n}{x^n} + o\left( { { x^n}} \right) \) D: \( {1 \over {1 + x}} = 1 - x - { { {x^2}} \over 2}- \cdots - { { {x^n}} \over {n!}} + o\left( { { x^n}} \right) \)

    • 4

      函数\(y = \sqrt {1{\rm{ - }}x} \)的导数为( ). A: \({\rm{ - }}{1 \over {2\sqrt {1{\rm{ - }}x} }}\) B: \({1 \over {2\sqrt {1{\rm{ - }}x} }}\) C: \({1 \over {\sqrt {1{\rm{ - }}x} }}\) D: \( - {1 \over {\sqrt {1{\rm{ - }}x} }}\)