The value of of $\int\limits_0^1 xe^x\,dx$ is:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 1
Evaluate:
$\displaystyle \int_0^1 x e^x \, dx$
Use integration by parts:
Let:
$u = x \quad \Rightarrow \quad du = dx$
$dv = e^x dx \quad \Rightarrow \quad v = e^x$
Then:
$\int x e^x \, dx = x e^x - \int e^x \, dx = x e^x - e^x + C$
Evaluate definite integral:
$\int_0^1 x e^x \, dx = \left[ x e^x - e^x \right]_0^1 = (1 \cdot e^1 - e^1) - (0 \cdot e^0 - e^0) = (e - e) - (0 - 1) = 0 - (-1) = 1$