Primitive of x squared by Exponential of x/Proof 1

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Theorem

$\ds \int x^2 e^x \rd x = e^x \paren {x^2 - 2 x + 2} + C$


Proof

From Primitive of $x^2 e^{a x}$:

$\ds \int x^2 e^{a x} \rd x = \frac {e^{a x} } a \paren {x^2 - \frac {2 x} a + \frac 2 {a^2} } + C$


The result follows by setting $a = 1$.

$\blacksquare$