本次共计算 1 个题目:每一题对 x 求 3 阶导数。
注意,变量是区分大小写的。\[ \begin{equation}\begin{split}【1/1】求函数\frac{{x}^{4}}{(1 + x)} 关于 x 的 3 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &原函数 = \frac{x^{4}}{(x + 1)}\\&\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( \frac{x^{4}}{(x + 1)}\right)}{dx}\\=&(\frac{-(1 + 0)}{(x + 1)^{2}})x^{4} + \frac{4x^{3}}{(x + 1)}\\=&\frac{-x^{4}}{(x + 1)^{2}} + \frac{4x^{3}}{(x + 1)}\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( \frac{-x^{4}}{(x + 1)^{2}} + \frac{4x^{3}}{(x + 1)}\right)}{dx}\\=&-(\frac{-2(1 + 0)}{(x + 1)^{3}})x^{4} - \frac{4x^{3}}{(x + 1)^{2}} + 4(\frac{-(1 + 0)}{(x + 1)^{2}})x^{3} + \frac{4*3x^{2}}{(x + 1)}\\=&\frac{2x^{4}}{(x + 1)^{3}} - \frac{8x^{3}}{(x + 1)^{2}} + \frac{12x^{2}}{(x + 1)}\\\\ &\color{blue}{函数的第 3 阶导数:} \\&\frac{d\left( \frac{2x^{4}}{(x + 1)^{3}} - \frac{8x^{3}}{(x + 1)^{2}} + \frac{12x^{2}}{(x + 1)}\right)}{dx}\\=&2(\frac{-3(1 + 0)}{(x + 1)^{4}})x^{4} + \frac{2*4x^{3}}{(x + 1)^{3}} - 8(\frac{-2(1 + 0)}{(x + 1)^{3}})x^{3} - \frac{8*3x^{2}}{(x + 1)^{2}} + 12(\frac{-(1 + 0)}{(x + 1)^{2}})x^{2} + \frac{12*2x}{(x + 1)}\\=&\frac{-6x^{4}}{(x + 1)^{4}} + \frac{24x^{3}}{(x + 1)^{3}} - \frac{36x^{2}}{(x + 1)^{2}} + \frac{24x}{(x + 1)}\\ \end{split}\end{equation} \]你的问题在这里没有得到解决?请到 热门难题 里面看看吧!