Question

Найти неопределенный интеграл

Answer 1

$\displaystyle \int (3x+ 9)^{6} dx = \left|\begin{array}{ccc}3x + 9 = t\\x = \dfrac{t}{3} - 3 \\ dx = \dfrac{dt}{3} \ \ \ \\\end{array}\right| = \int t^{6} \cdot \dfrac{dt}{3} = \dfrac{1}{3} \int t^{6} \, dt = \dfrac{1}{3} \cdot \dfrac{t^{7}}{7} + C =\\ = \dfrac{(3x + 9)^{7}}{21} + C$

$\displaystyle \int (5x^{3} - 4x^{2} + 7x^{4}) \, dx = \dfrac{5x^{4}}{4} - \dfrac{4x^{3}}{3} + \dfrac{7x^{5}}{5} + C$