Question

高数求解，这题为什么选C，谢谢了

请看图

Answer 1

(3) x ≥ 0 时， I = ∫xdx = (1/2)x^2 + C = (1/2)x·x + C
x < 0 时， I = ∫-xdx = (-1/2)x^2 + C = (1/2)(-x)x + C
故选 C

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谢谢