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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

Choose the correct answer from the given alternatives in the following question: If A = cossinsincos[cosα-sinαsinαcosα], then A-1 = _____ - Mathematics and Statistics

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प्रश्न

Choose the correct answer from the given alternatives in the following question:

If A = `[("cos"alpha,-"sin"alpha),("sin"alpha,"cos"alpha)]`, then A-1 = _____

पर्याय

  • `[(1/("cos"alpha),-1/("sin" alpha)),(1/("sin"alpha),1/("cos"alpha))]`

  • `[("cos"alpha,"sin"alpha),(-"sin"alpha, "cos"alpha)]`

  • `[(-"cos"alpha,"sin"alpha),(-"sin"alpha, "cos"alpha)]`

  • `[(-"cos"alpha,"sin"alpha),("sin"alpha, -"cos"alpha)]`

MCQ

उत्तर

`[("cos"alpha,"sin"alpha),(-"sin"alpha, "cos"alpha)]`

Explanation:

A = `[("cos"alpha,-"sin"alpha),("sin"alpha,"cos"alpha)]`

|A| = cos2α + sin2α = 1

A−1 = `1/|"A"| "Adj"("A") = 1/1 [("cos"alpha,"sin"alpha),(-"sin"alpha, "cos"alpha)]`

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पाठ 2: Matrics - Miscellaneous exercise 2 (B) [पृष्ठ ६२]

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