本次共计算 1 个题目:每一题对 y 求 3 阶导数。
注意,变量是区分大小写的。\[ \begin{equation}\begin{split}【1/1】求函数\frac{(ln(x + y + 1))}{(1 + {y}^{2})} 关于 y 的 3 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &原函数 = \frac{ln(x + y + 1)}{(y^{2} + 1)}\\&\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( \frac{ln(x + y + 1)}{(y^{2} + 1)}\right)}{dy}\\=&(\frac{-(2y + 0)}{(y^{2} + 1)^{2}})ln(x + y + 1) + \frac{(0 + 1 + 0)}{(y^{2} + 1)(x + y + 1)}\\=&\frac{-2yln(x + y + 1)}{(y^{2} + 1)^{2}} + \frac{1}{(x + y + 1)(y^{2} + 1)}\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( \frac{-2yln(x + y + 1)}{(y^{2} + 1)^{2}} + \frac{1}{(x + y + 1)(y^{2} + 1)}\right)}{dy}\\=&-2(\frac{-2(2y + 0)}{(y^{2} + 1)^{3}})yln(x + y + 1) - \frac{2ln(x + y + 1)}{(y^{2} + 1)^{2}} - \frac{2y(0 + 1 + 0)}{(y^{2} + 1)^{2}(x + y + 1)} + \frac{(\frac{-(0 + 1 + 0)}{(x + y + 1)^{2}})}{(y^{2} + 1)} + \frac{(\frac{-(2y + 0)}{(y^{2} + 1)^{2}})}{(x + y + 1)}\\=&\frac{8y^{2}ln(x + y + 1)}{(y^{2} + 1)^{3}} - \frac{2ln(x + y + 1)}{(y^{2} + 1)^{2}} - \frac{2y}{(x + y + 1)(y^{2} + 1)^{2}} - \frac{2y}{(y^{2} + 1)^{2}(x + y + 1)} - \frac{1}{(x + y + 1)^{2}(y^{2} + 1)}\\\\ &\color{blue}{函数的第 3 阶导数:} \\&\frac{d\left( \frac{8y^{2}ln(x + y + 1)}{(y^{2} + 1)^{3}} - \frac{2ln(x + y + 1)}{(y^{2} + 1)^{2}} - \frac{2y}{(x + y + 1)(y^{2} + 1)^{2}} - \frac{2y}{(y^{2} + 1)^{2}(x + y + 1)} - \frac{1}{(x + y + 1)^{2}(y^{2} + 1)}\right)}{dy}\\=&8(\frac{-3(2y + 0)}{(y^{2} + 1)^{4}})y^{2}ln(x + y + 1) + \frac{8*2yln(x + y + 1)}{(y^{2} + 1)^{3}} + \frac{8y^{2}(0 + 1 + 0)}{(y^{2} + 1)^{3}(x + y + 1)} - 2(\frac{-2(2y + 0)}{(y^{2} + 1)^{3}})ln(x + y + 1) - \frac{2(0 + 1 + 0)}{(y^{2} + 1)^{2}(x + y + 1)} - \frac{2(\frac{-(0 + 1 + 0)}{(x + y + 1)^{2}})y}{(y^{2} + 1)^{2}} - \frac{2(\frac{-2(2y + 0)}{(y^{2} + 1)^{3}})y}{(x + y + 1)} - \frac{2}{(x + y + 1)(y^{2} + 1)^{2}} - \frac{2(\frac{-2(2y + 0)}{(y^{2} + 1)^{3}})y}{(x + y + 1)} - \frac{2(\frac{-(0 + 1 + 0)}{(x + y + 1)^{2}})y}{(y^{2} + 1)^{2}} - \frac{2}{(y^{2} + 1)^{2}(x + y + 1)} - \frac{(\frac{-2(0 + 1 + 0)}{(x + y + 1)^{3}})}{(y^{2} + 1)} - \frac{(\frac{-(2y + 0)}{(y^{2} + 1)^{2}})}{(x + y + 1)^{2}}\\=&\frac{-48y^{3}ln(x + y + 1)}{(y^{2} + 1)^{4}} + \frac{24yln(x + y + 1)}{(y^{2} + 1)^{3}} + \frac{8y^{2}}{(x + y + 1)(y^{2} + 1)^{3}} + \frac{16y^{2}}{(y^{2} + 1)^{3}(x + y + 1)} + \frac{4y}{(x + y + 1)^{2}(y^{2} + 1)^{2}} + \frac{2y}{(y^{2} + 1)^{2}(x + y + 1)^{2}} - \frac{4}{(x + y + 1)(y^{2} + 1)^{2}} + \frac{2}{(x + y + 1)^{3}(y^{2} + 1)} - \frac{2}{(y^{2} + 1)^{2}(x + y + 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!