∫ from 0 to ∞ e^(-x) dx =
A0
Be
C1 (improper integral, [-e^(-x)] from 0 to ∞)
D∞
Answer & Solution
Correct answer: C. 1 (improper integral, [-e^(-x)] from 0 to ∞)
∫₀^∞ e^(-x) dx = lim_(b→∞) [-e^(-x)]₀^b = lim (1 - e^(-b)) = 1. Improper but convergent. Used in exponential probability distributions.
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