Подробное решение
Не могу найти шаги в поиске этой производной.
Но производная
Ответ:
atan(7*x) /atan(7*x) 7*log(x)\
x *|--------- + ---------|
| x 2|
\ 1 + 49*x /
$$x^{\operatorname{atan}{\left (7 x \right )}} \left(\frac{7 \log{\left (x \right )}}{49 x^{2} + 1} + \frac{1}{x} \operatorname{atan}{\left (7 x \right )}\right)$$
/ 2 \
atan(7*x) |/atan(7*x) 7*log(x)\ atan(7*x) 14 686*x*log(x)|
x *||--------- + ---------| - --------- + ------------- - ------------|
|| x 2| 2 / 2\ 2|
|\ 1 + 49*x / x x*\1 + 49*x / / 2\ |
\ \1 + 49*x / /
$$x^{\operatorname{atan}{\left (7 x \right )}} \left(- \frac{686 x \log{\left (x \right )}}{\left(49 x^{2} + 1\right)^{2}} + \left(\frac{7 \log{\left (x \right )}}{49 x^{2} + 1} + \frac{1}{x} \operatorname{atan}{\left (7 x \right )}\right)^{2} + \frac{14}{x \left(49 x^{2} + 1\right)} - \frac{1}{x^{2}} \operatorname{atan}{\left (7 x \right )}\right)$$
/ 3 2 \
atan(7*x) |/atan(7*x) 7*log(x)\ 2058 686*log(x) 21 /atan(7*x) 7*log(x)\ /atan(7*x) 14 686*x*log(x)\ 2*atan(7*x) 134456*x *log(x)|
x *||--------- + ---------| - ------------ - ------------ - -------------- - 3*|--------- + ---------|*|--------- - ------------- + ------------| + ----------- + ----------------|
|| x 2| 2 2 2 / 2\ | x 2| | 2 / 2\ 2| 3 3 |
|\ 1 + 49*x / / 2\ / 2\ x *\1 + 49*x / \ 1 + 49*x / | x x*\1 + 49*x / / 2\ | x / 2\ |
\ \1 + 49*x / \1 + 49*x / \ \1 + 49*x / / \1 + 49*x / /
$$x^{\operatorname{atan}{\left (7 x \right )}} \left(\frac{134456 x^{2} \log{\left (x \right )}}{\left(49 x^{2} + 1\right)^{3}} + \left(\frac{7 \log{\left (x \right )}}{49 x^{2} + 1} + \frac{1}{x} \operatorname{atan}{\left (7 x \right )}\right)^{3} - 3 \left(\frac{7 \log{\left (x \right )}}{49 x^{2} + 1} + \frac{1}{x} \operatorname{atan}{\left (7 x \right )}\right) \left(\frac{686 x \log{\left (x \right )}}{\left(49 x^{2} + 1\right)^{2}} - \frac{14}{x \left(49 x^{2} + 1\right)} + \frac{1}{x^{2}} \operatorname{atan}{\left (7 x \right )}\right) - \frac{686 \log{\left (x \right )}}{\left(49 x^{2} + 1\right)^{2}} - \frac{2058}{\left(49 x^{2} + 1\right)^{2}} - \frac{21}{x^{2} \left(49 x^{2} + 1\right)} + \frac{2}{x^{3}} \operatorname{atan}{\left (7 x \right )}\right)$$