MCQ
The value of the integral $\int\limits_0^\infty  {} $ $e ^{-2x}\, (\sin\, 2x + \cos\, 2x)\, dx =$
  • A
    $1$
  • B
    $- 2$
  • $1/2$
  • D
    zero

Answer

Correct option: C.
$1/2$
c
Put $- 2 x = t$ and use $\int \, e^x ( f (x) + f ‘ (x) ) d x = e^x f (x) + c$]

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