∫ dx/(x² + 4) equals:
Aarctan(x) + C
Barctan(x/2) + C
C(1/4) arctan(x) + C
D(1/2) arctan(x/2) + C
Answer & Solution
Correct answer: D. (1/2) arctan(x/2) + C
∫ dx/(x² + a²) = (1/a) arctan(x/a) + C. With a² = 4, a = 2: (1/2) arctan(x/2) + C.
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