∫ x 4 e x ∫ x n e x d x = x n e x − n ∫ x n − 1 e x d x x 4 e x − 4 ∫ x 3 e x d x {\displaystyle {\begin{aligned}&\int {}^{}x^{4}e^{x}&\int {}^{}x^{n}e^{x}dx=x^{n}e^{x}-n\int {}^{}x^{n-1}e^{x}dx&x^{4}e^{x}-4\int {}^{}x^{3}e^{x}dx\end{aligned}}}
