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If A is an invertible matrix of order 2, then det (A−1) is equal to ______. - Mathematics

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प्रश्न

If A is an invertible matrix of order 2, then det (A−1) is equal to ______.

विकल्प

  • det (A)

  • `1/det (A)`

  • 1

  • 0

MCQ
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उत्तर

If A is an invertible matrix of order 2, then det (A−1) is equal to `underline(1/det (A))`.

Explanation:

`because` A invertible matrix `=> abs "A" ne 0`

`therefore "AA"^-1 = "I"` and `abs ("AA"^-1) = abs "I" = 1`

`=> abs "A" abs ("A"^-1) = 1` 

`=> abs ("A"^-1) = 1/abs "A"` 

`=> det ("A"^-1) = 1/det("A")`

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Determinants - Exercise 4.5 [पृष्ठ १३२]

APPEARS IN

एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
अध्याय 4 Determinants
Exercise 4.5 | Q 18 | पृष्ठ १३२

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