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The time to failure in thousands of hours of an electronic equipment used in a manufactured computer has the density functioneeleswheref(x)={3e-3xx>00eleswhereFind the expected life of this electronic

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प्रश्न

The time to failure in thousands of hours of an electronic equipment used in a manufactured computer has the density function
`f(x) = {{:(3"e"^(-3x), x > 0),(0, "eleswhere"):}`
Find the expected life of this electronic equipment

बेरीज
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उत्तर

`mu = "E"("X")`

= `int_0^oo x f(x) "d"x`

= `3 int_0^oo x"e"^(-3x) "d"x`

u = x, `int"dv" = int"e"^(-3x)"d"x`

du = dx, v = `"e"^(-3x)/(-3)`

`int"udv" = "uv" - int"vdu"`

= `3[(x"e"^(-3x))/(-3) + int"e"^(-3x)/3 "d"x]_0^oo`

= `3[- (x"e"^(-3x))/3 - "e"^(-3x)/9]_0^oo`

= `3[0 - (0 - 1/9)]`

= `1/3`

Expected life of the electronic equipment = `1/3`

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Mathematical Expectation
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 11: Probability Distributions - Exercise 11.4 [पृष्ठ २१०]

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सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 12 TN Board
पाठ 11 Probability Distributions
Exercise 11.4 | Q 6 | पृष्ठ २१०

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