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The value of integral \(\int_{-2}^{+2} x\, e^{-2x^{2}}\, dx\) is

  • A.0
  • B.\(\frac{1}{2}\)
  • C.1
  • D.2

Answer: A

The integral equals 0.

The integrand \(f(x) = x\,e^{-2x^{2}}\) is odd: \(f(-x) = -x\,e^{-2x^{2}} = -f(x)\). The integral of an odd function over limits symmetric about zero vanishes, because the area for negative x exactly cancels the area for positive x.

Directly, with \(u = -2x^{2}\):

\[ \int x\,e^{-2x^{2}}\,dx = -\tfrac{1}{4}e^{-2x^{2}} \]

which takes the same value at x = +2 and x = −2, so the difference is zero. The value 1/2 would come from integrating only from 0 to infinity and doubling, which ignores the sign of x.

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