本次共计算 5 个题目:每一题对 x 求 2 阶导数。
注意,变量是区分大小写的。\[ \begin{equation}\begin{split}【1/5】求函数xx 关于 x 的 2 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &原函数 = x^{2}\\&\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( x^{2}\right)}{dx}\\=&2x\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( 2x\right)}{dx}\\=&2\\ \end{split}\end{equation} \]\[ \begin{equation}\begin{split}【2/5】求函数xsin(x) 关于 x 的 2 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( xsin(x)\right)}{dx}\\=&sin(x) + xcos(x)\\=&sin(x) + xcos(x)\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( sin(x) + xcos(x)\right)}{dx}\\=&cos(x) + cos(x) + x*-sin(x)\\=&2cos(x) - xsin(x)\\ \end{split}\end{equation} \]\[ \begin{equation}\begin{split}【3/5】求函数xlog_{x}^{xx} 关于 x 的 2 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &原函数 = xlog_{x}^{x^{2}}\\&\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( xlog_{x}^{x^{2}}\right)}{dx}\\=&log_{x}^{x^{2}} + x(\frac{(\frac{(2x)}{(x^{2})} - \frac{(1)log_{x}^{x^{2}}}{(x)})}{(ln(x))})\\=& - \frac{log_{x}^{x^{2}}}{ln(x)} + \frac{2}{ln(x)} + log_{x}^{x^{2}}\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( - \frac{log_{x}^{x^{2}}}{ln(x)} + \frac{2}{ln(x)} + log_{x}^{x^{2}}\right)}{dx}\\=& - \frac{(\frac{(\frac{(2x)}{(x^{2})} - \frac{(1)log_{x}^{x^{2}}}{(x)})}{(ln(x))})}{ln(x)} - \frac{log_{x}^{x^{2}}*-1}{ln^{2}(x)(x)} + \frac{2*-1}{ln^{2}(x)(x)} + (\frac{(\frac{(2x)}{(x^{2})} - \frac{(1)log_{x}^{x^{2}}}{(x)})}{(ln(x))})\\=& - \frac{4}{xln^{2}(x)} + \frac{2log_{x}^{x^{2}}}{xln^{2}(x)} + \frac{2}{xln(x)} - \frac{log_{x}^{x^{2}}}{xln(x)}\\ \end{split}\end{equation} \]\[ \begin{equation}\begin{split}【4/5】求函数xsin(x)cos(x) 关于 x 的 2 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( xsin(x)cos(x)\right)}{dx}\\=&sin(x)cos(x) + xcos(x)cos(x) + xsin(x)*-sin(x)\\=&sin(x)cos(x) + xcos^{2}(x) - xsin^{2}(x)\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( sin(x)cos(x) + xcos^{2}(x) - xsin^{2}(x)\right)}{dx}\\=&cos(x)cos(x) + sin(x)*-sin(x) + cos^{2}(x) + x*-2cos(x)sin(x) - sin^{2}(x) - x*2sin(x)cos(x)\\=&2cos^{2}(x) - 2sin^{2}(x) - 4xsin(x)cos(x)\\ \end{split}\end{equation} \]\[ \begin{equation}\begin{split}【5/5】求函数sin(cos(x)) 关于 x 的 2 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( sin(cos(x))\right)}{dx}\\=&cos(cos(x))*-sin(x)\\=&-sin(x)cos(cos(x))\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( -sin(x)cos(cos(x))\right)}{dx}\\=&-cos(x)cos(cos(x)) - sin(x)*-sin(cos(x))*-sin(x)\\=&-cos(x)cos(cos(x)) - sin(cos(x))sin^{2}(x)\\ \end{split}\end{equation} \]你的问题在这里没有得到解决?请到 热门难题 里面看看吧!