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

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Question

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

f(x) = x, for 0 ≤ x ≤ 1 and 2 - x for 1 < x < 2

Sum
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Solution

f (x) ≥ 0

`int_0^2 f(x) dx = int_0^1 f(x) dx + int_1^2 f(x) dx`

 = `int_0^1 x dx + int_1^2 (2 - x) dx`

= `[x^2/2]_0^1 + [2x - x^2/2]_1^2 ` 

= `1^2/2 - 0^2/2 + (2 xx2 - 2^2/2) - (2 (1) - 1^2/2)`

= `1/2 - 0 + (4 - 2) - (2 - 1/2)  `

= `1/2 + 2 - 3/2`

= `-2/2 + 2`

= - 1+ 2

= 1

∴ f (x) is p.d.f

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Probability Distribution of a Continuous Random Variable
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Chapter 7: Probability Distributions - Exercise 7.2 [Page 238]

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