silemus.

28Integration by parts

Use integration by parts to evaluate ∫01xex dx\displaystyle \int_0^1 x e^x\,dx.

Split x·eˣ using parts: u = x, dv = eˣdx, so du = dx, v = eˣ. This gives [xeˣ]₀¹ − ∫eˣdx = e − (e−1) = 1. Checking: e − (e−1) ≈ 2.718 − 1.718 = 1.

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