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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

Verify which of the following is p.d.f. of r.v. X: (i) f(x) = sin x, for 0 ≤ x ≤ ππ2 (ii) f(x) = x, for 0 ≤ x ≤ 1 and -2 -x for 1 < x < 2 (iii) f(x) = 2, for 0 ≤ x ≤ 1. - Mathematics and Statistics

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प्रश्न

Verify which of the following is p.d.f. of r.v. X:

 f(x) = sin x, for 0 ≤ x ≤ `π/2`

बेरीज
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उत्तर

(a) f(x) = sin x ≥ 0 if 0 ≤ x ≤ `π/2`

(b) `int_(-∞)^∞ f(x) dx =  int_(-∞)^0 f(x) dx + int_(-∞)^(π/2) f(x) dx + int_( π/2)^∞ f(x) dx`

= `0 +int_(0)^(π/2) sinx  dx + 0`

= `[-cosx]_0^(π/2) = -cos(π/2) + cos0 = 0 + 1 = 1`

Hence, f(x) is the p.d.f. of X.

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Probability Distribution of a Continuous Random Variable
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 7: Probability Distributions - Exercise 7.2 [पृष्ठ २३८]

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