本次共计算 1 个题目:每一题对 z 求 2 阶导数。
注意,变量是区分大小写的。\[ \begin{equation}\begin{split}【1/1】求函数{(aa + zz)}^{\frac{-3}{2}} - {(aa + zz - 2zb + bb)}^{\frac{-3}{2}} 关于 z 的 2 阶导数:\\\end{split}\end{equation} \]
\[ \begin{equation}\begin{split}\\解:&\\ &原函数 = \frac{1}{(a^{2} + z^{2})^{\frac{3}{2}}} - \frac{1}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{3}{2}}}\\&\color{blue}{函数的第 1 阶导数:}\\&\frac{d\left( \frac{1}{(a^{2} + z^{2})^{\frac{3}{2}}} - \frac{1}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{3}{2}}}\right)}{dz}\\=&(\frac{\frac{-3}{2}(0 + 2z)}{(a^{2} + z^{2})^{\frac{5}{2}}}) - (\frac{\frac{-3}{2}(0 + 2z - 2b + 0)}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{5}{2}}})\\=&\frac{-3z}{(a^{2} + z^{2})^{\frac{5}{2}}} + \frac{3z}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{5}{2}}} - \frac{3b}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{5}{2}}}\\\\ &\color{blue}{函数的第 2 阶导数:} \\&\frac{d\left( \frac{-3z}{(a^{2} + z^{2})^{\frac{5}{2}}} + \frac{3z}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{5}{2}}} - \frac{3b}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{5}{2}}}\right)}{dz}\\=&-3(\frac{\frac{-5}{2}(0 + 2z)}{(a^{2} + z^{2})^{\frac{7}{2}}})z - \frac{3}{(a^{2} + z^{2})^{\frac{5}{2}}} + 3(\frac{\frac{-5}{2}(0 + 2z - 2b + 0)}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{7}{2}}})z + \frac{3}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{5}{2}}} - 3(\frac{\frac{-5}{2}(0 + 2z - 2b + 0)}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{7}{2}}})b + 0\\=&\frac{15z^{2}}{(a^{2} + z^{2})^{\frac{7}{2}}} - \frac{15z^{2}}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{7}{2}}} + \frac{30bz}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{7}{2}}} - \frac{15b^{2}}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{7}{2}}} + \frac{3}{(a^{2} + z^{2} - 2bz + b^{2})^{\frac{5}{2}}} - \frac{3}{(a^{2} + z^{2})^{\frac{5}{2}}}\\ \end{split}\end{equation} \]你的问题在这里没有得到解决?请到 热门难题 里面看看吧!