English

D∫-22|xcosπx|dx is equal to ______.

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Question

`int_(-2)^2 |x cos pix| "d"x` is equal to ______.

Options

  • `8/pi`

  • `4/pi`

  • `2/pi`

  • `1/pi`

MCQ
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Solution

`int_(-2)^2 |x cos pix| "d"x` is equal to `8/pi`.

Explanation:

Since I = `int_(-2)^2 |x cos pix| "d"x`

= `2 int_0^2 |x cos pix| "d"x`

= `2 {int_0^(1/2) |x cos pix|"d"x + int_(1/2)^(3/2) |x cos pix| "d"x + int_(3/2)^2 |x cos pix| "d"x}`

= `8/pi`

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Chapter 7: Integrals - Solved Examples [Page 162]

APPEARS IN

NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 7 Integrals
Solved Examples | Q 28 | Page 162

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